+This document details the changes between this version, bash-4.3-release, and
+the previous version, bash-4.3-rc2.
+
+1. Changes to Bash
+
+a. Only Posix-mode shells should exit on an assignment failure in the
+ temporary environment preceding a special builtin. This is how it's been
+ documented.
+
+b. Fixed a bug that caused a failed special builtin to not exit a posix-mode
+ shell if the failing builtin was on the LHS of a && or ||.
+
+c. Changed the handling of unquoted backslashes in regular expressions to be
+ closer to bash-4.2.
+
+d. globstar (**) no longer traverses symbolic links that resolve to
+ directories. This eliminates some duplicate entries.
+
+e. Fixed a bug that caused a SIGCHLD trap handler to not be able to change the
+ SIGCHLD disposition.
+
+f. Fixed a bug that caused a crash when -x was enabled and a command
+ contained a printable multibyte (wide) character.
+
+g. Fixed a bug that caused an interactive shell without line editing enabled
+ to read invalid data after receiving a SIGINT.
+
+h. Fixed a bug that caused command word completion to fail if the directory in
+ $PATH where the completion would be found contained single or double quotes.
+
+i. Fixed a bug that caused a shell with -v enabled to print commands in $()
+ multiple times.
+
+2. Changes to Readline
+
+a. Fixed a bug that caused `undo' to reference freed memory or null pointers.
+
+3. New Features in Bash
+
+a. The [[ -v ]] option now understands array references (foo[1]) and returns
+ success if the referenced element has a value.
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-4.3-rc2, and the
+previous version, bash-4.3-rc1.
+
+1. Changes to Bash
+
+a. Fixed a bug that left variables set by printf -v marked as invisible.
+
+b. Fixed an off-by-one error in a job control warning message.
+
+c. Fixed a bug that caused the shell to crash after declaring a nameref variable
+ without a value.
+
+d. Fixed a bug that caused asynchronous commands to not set $? correctly.
+
+e. Fixed a bug that caused out-of-order execution when executing aliases with
+ embedded newlines containing `.' commands.
+
+f. Fixed a bug that caused error messages generated by expansion errors in
+ `for' commands to have the wrong line number.
+
+g. Fixed a bug that caused the `wait' builtin to not be interruptible in an
+ interactive shell with job control enabled.
+
+h. Fixed a bug that caused SIGINT and SIGQUIT to not be trappable in
+ asynchronous subshell commands.
+
+i. Bash now requires that the value assigned to a nameref variable be a valid
+ shell identifier (variable name or array reference).
+
+j. Converting an existing variable to a nameref variable now turns off the
+ -i/-l/-u/-c attributes.
+
+k. Displaying a nameref variable with `declare -p' now displays the nameref
+ variable and its value rather than following the nameref chain.
+
+l. Fixed a problem with interrupt handling that caused a second and subsequent
+ SIGINT to be ignored by interactive shells.
+
+m. Fixed a bug that caused certain positional parameter and array expansions
+ to mishandle (discard) null positional parameters and array elements.
+
+n. The shell no longer blocks receipt of signals while running trap handlers
+ for those signals, and allows most trap handlers to be run recursively
+ (running trap handlers while a trap handler is executing).
+
+o. The shell now handles backslashes in regular expression arguments to the
+ [[ command's =~ operator slightly differently, resulting in more
+ consistent behavior.
+
+2. Changes to Readline
+
+a. Fixed a bug that could cause readline to crash and seg fault attempting to
+ expand an empty history entry.
+
+b. Fixed a bug that caused a bad entry in the $LS_COLORS variable to abort all
+ color processing but leave color enabled.
+
+c. Fixed a bug that caused display problems with multi-line prompts containing
+ invisible characters on multiple lines.
+
+d. Fixed a bug that caused effects made by undoing changes to a history line to
+ be discarded.
+
+3. New Features in Bash
+
+4. New Features in Readline
+
+a. When creating shared libraries on Mac OS X, the pathname written into the
+ library (install_name) no longer includes the minor version number.
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-4.3-rc1, and the
+previous version, bash-4.3-beta2.
+
+1. Changes to Bash
+
+a. Fixed a bug in bash completion that caused a tilde to be expanded even if
+ the `direxpand' option was not enabled.
+
+b. Fixed a potential bug that could cause corrupted input in interactive shells
+ running without line editing and with `ignoreeof' enabled.
+
+c. Fixed a bug that could cause failures when opening pipes back to shells
+ created to run process substitutions.
+
+d. Fixed a bug that caused an assignment to TEXTDOMAIN to require TEXTDOMAINDIR
+ to be set in order to actually change the current text domain.
+
+e. Changed the way redirections are printed to avoid confusion when the target
+ of an output redirection is a process substitution beginning with `>'.
+
+2. Changes to Readline
+
+a. Shared library building is now supported on Mac OS X 10.9 (Darwin 13).
+
+3. New Features in Bash
+
+a. `cd' has a new `-@' option to browse a file's extended attributes on
+ systems that support O_XATTR.
+
+4. New Features in Readline
+
+a. There are additional default key bindings for MinGW32
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-4.3-beta2, and the
+previous version, bash-4.3-beta.
+
+1. Changes to Bash
+
+a. Fixed a bug that caused assignment to an unset variable using a negative
+ subscript to result in a segmentation fault.
+
+b. Fixed a bug that caused assignment to a string variable using a negative
+ subscript to use the incorrect index.
+
+c. Fixed a bug that caused some strings to be interpreted as invalid
+ extended globbing expressions when used with the help builtin.
+
+d. Fixed a bug that caused an attempt to trap a signal whose disposition
+ cannot be changed to reference uninitialized memory.
+
+e. Command completion now skips assignment statements preceding a command
+ name and completes the command.
+
+f. Fixed a bug that caused `compgen -f' in a non-interactive shell to dump
+ core under certain circumstances.
+
+g. Fixed a bug that caused the `read -N' to misbehave when the input stream
+ contains 0xff.
+
+2. Changes to Readline
+
+a. Changed message when an incremental search fails to include "failed" in
+ the prompt and display the entire search string instead of just the last
+ matching portion.
+
+b. Fixed a bug that caused an arrow key typed to an incremental search prompt
+ to process the key sequence incorrectly.
+
+c. Additional key bindings for arrow keys on MinGW.
+
+3. New Features in Bash
+
+a. The help builtin now attempts substring matching (as it did through
+ bash-4.2) if exact string matching fails.
+
+b. The fc builtin now interprets -0 as the current command line.
+
+c. Completing directory names containing shell variables now adds a trailing
+ slash if the expanded result is a directory.
+
+4. New Features in Readline
+
+a. rl_change_environment: new application-settable variable that controls
+ whether or not Readline modifies the environment (currently readline
+ modifies only LINES and COLUMNS).
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-4.3-beta, and the
+previous version, bash-4.3-alpha.
+
+1. Changes to Bash
+
+a. Fixed a bug in the prompt directory name "trimming" code that caused
+ memory corruption and garbled the results.
+
+b. Fixed a bug that caused single quotes that resulted from $'...' quoting
+ in the replacement portion of a double-quoted ${word/pat/rep} expansion
+ to be treated as quote characters.
+
+c. Fixed a bug that caused assignment statements preceding a command word to
+ result in assignment statements following a declaration command to not be
+ expanded like assignment statements.
+
+d. Fixed a bug with variable search order in the presence of local variables
+ with the same name as variables in the temporary environment supplied to
+ a shell function.
+
+e. Fixed a bug that caused constructs like 1<(2) to be interpreted as process
+ substitutions even in an arithmetic context.
+
+f. Fixed several cases where `invisible' variables (variables with attributes
+ but no values, which are technically unset) were treated incorrectly.
+
+g. Fixed a bug that caused group commands in pipelines that were not the
+ last element to not run the EXIT trap.
+
+h. Fixed a bug that caused `unset -n' to not unset a nameref variable in
+ certain cases.
+
+i. Fixed the nameref circular reference checking to be less strict and only
+ disallow a nameref variable with the same value as its name at the global
+ scope.
+
+j. Fixed a bug that caused trap handlers to be executed recursively,
+ corrupting internal data structures.
+
+k. Fixed a bug that could result in bash not compiling if certain options were
+ not enabled.
+
+l. Fixed a bug that caused the arithmetic expansion code to attempt variable
+ assignments when operator precedence prohibited them.
+
+m. Word expansions like ${foo##bar} now understand indirect variable references.
+
+n. Fixed a bug that caused `declare -fp name' to not display a function
+ definition.
+
+o. Fixed a bug that caused asynchronous child processes to modify the stdin
+ file pointer when bash was using it to read a script, which modified the
+ parent's value as well.
+
+2. Changes to Readline
+
+a. Fixed a bug in vi mode that caused the arrow keys to set the saved last
+ vi-mode command to the wrong value.
+
+b. Fixed a bug that caused double-quoted strings to be scanned incorrectly
+ when being used as the value of a readline variable assignment.
+
+c. Fixed a bug with vi mode that prevented `.' from repeating a command
+ entered on a previous line (command).
+
+d. Fixed a bug that could cause completion to core dump if it was interrupted
+ by a signal.
+
+e. Readline now sends the meta-key enable string to the terminal if the
+ terminal has been successfully initialized.
+
+f. Readline now calls the signal hook after resizing the terminal when it
+ receives a SIGWINCH.
+
+g. Fixed a bug that could cause the history list code to perform an out-of-
+ bounds array reference if the history list is empty.
+
+3. New Features in Bash
+
+a. Shells started to run process substitutions now run any trap set on EXIT.
+
+b. There is now a configure-time option to enable the globasciiranges option
+ by default.
+
+c. The read builtin now checks its first variable argument for validity before
+ trying to read any input.
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-4.3-alpha,
+and the previous version, bash-4.2-release.
+
+1. Changes to Bash
+
+a. Fixed several bugs concerning incomplete bracket expressions in filename
+ generation (globbing) patterns.
+
+b. Fixed a bug with single quotes and WORD in ${param op WORD} when running
+ in Posix mode.
+
+c. Fixed a bug that caused the pattern removal and pattern substitution word
+ expansions and case statement word expansion to not match the empty string.
+
+d. Fixed a bug that caused the tzset() function to not work after changing
+ the TZ enviroment variable.
+
+e. Fixed a bug that caused the RHS of an assignment statement to undergo
+ word splitting when it contained an unquoted $@.
+
+f. Fixed bugs that caused the shell to not react to a SIGINT sent while
+ waiting for a child process to exit.
+
+g. Bash doesn't try to run things in a signal handler context when it gets a
+ signal (SIGINT/SIGHUP/etc) while reading input using readline but still
+ be responsive to terminating signals.
+
+h. Fixed a bug that caused bash to go into an infinite loop if a filename
+ to be matched contained an invalid multibyte character.
+
+i. Fixed a bug that caused PS4 to end up being truncated if it is longer
+ than 128 bytes.
+
+j. Fixed a bug that caused brace expansion to not skip over double-quoted
+ command substitution.
+
+k. System-specific updates for: DJGPP, HP/UX, Mac OS X
+
+l. Fixed a bug in displaying commands that caused redirections to be associated
+ with the wrong part of the command.
+
+m. Fixed the coproc cleanup to unset the appropriate shell variables when a
+ coproc terminates.
+
+n. Fixed a bug that caused `fc' to dump core due to incorrect calculation of
+ the last history entry.
+
+o. Added workarounds for FreeBSD's implementation of faccessat/eaccess and
+ `test -x'.
+
+p. Fixed a bug that caused the shell to not match patterns containing
+ control-A.
+
+q. Fixed a bug that could result in doubled error messages when the `printf'
+ builtin got a write error.
+
+r. Fixed a bug that caused the shell to not correctly expand words containing
+ multiple consecutive quoted empty strings (""""""aa).
+
+s. Fixed a bug that caused the shell to not correctly parse multi-line
+ process substitutions containing comments and quoted strings.
+
+t. Fixed a problem with the bash malloc's internal idea of the top of the
+ memory heap that resulted in incorrect decisions to try to reduce the
+ break and give memory back to the kernel.
+
+u. There are changes to the expansions peformed on compound array assignments,
+ in an effort to make foo=( [ind1]=bar [ind2]=baz ) identical to
+ foo[ind1]=bar foo[ind2]=baz.
+
+v. Bash now reports an error if `read -a name' is used when `name' is an
+ existing associative array.
+
+w. Fixed a bug that allowed an attempted assignment to a readonly variable
+ in an arithmetic expression to not return failure.
+
+x. Fixed several bugs that caused completion functions to be invoked even when
+ the cursor was before the first word in the command.
+
+y. Fixed a bug that caused parsing a command substitution to overwrite the
+ parsing state associated with the complete input line.
+
+z. Fixed several bugs with the built-in snprintf replacement and field widths
+ and floating point.
+
+aa. Fixed a bug that caused incorrect offset calculations and input buffer
+ corruption when reading files longer than 2^31 bytes.
+
+bb. Fixed several bugs where bash performed arithmetic evaluation in contexts
+ where evaluation is suppressed.
+
+cc. Fixed a bug that caused bash to close FIFOs used for process substitution
+ too early when a shell function was executing, but protect against using
+ all file descriptors when the shell functions are invoked inside loops.
+
+dd. Added checks for printable (and non-printable) multibyte characters for
+ use in error messages.
+
+ee. Fixed a bug that caused ^O (operate-and-get-next) to not work correctly
+ at the end of the history list.
+
+ff. Fixed a bug that caused command-oriented history to incorrectly combine
+ here documents into one line.
+
+gg. Fixed a bug that caused importing SHELLOPTS from the environment into a
+ Posix-mode shell to print an error message and refuse to parse it.
+
+hh. Fixed a bug that caused the shell to delete an extra history entry when
+ using `history -s'.
+
+ii. Fixed a bug that caused floating-point exceptions and overflow errors
+ for the / and % arithmetic operators when using INTMAX_MIN and -1.
+
+jj. Fixed a bug that caused parsing errors when reading an arithmetic for
+ loop inside a command substitution.
+
+kk. Fixed a bug that caused a readonly function to be unset when unset was
+ called without the -f or -v option.
+
+ll. Fixed several bugs in the code that quotes characters special to regular
+ expressions when used in a quoted string on the RHS of the =~ operator
+ to the [[ command.
+
+mm. Fixed a bug that caused redirections to fail because the file descriptor
+ limit was set to a value less than 10.
+
+nn. Fixed a bug that caused the `read' builtin to execute code in a signal
+ handler context if read timed out.
+
+oo. Fixed a bug that caused extended globbing patterns to not match files
+ beginning with `.' correctly when a `.' was explicitly supplied in the
+ pattern.
+
+pp. Fixed a bug that caused key sequences longer than two characters to not
+ work when used with `bind -x'.
+
+qq. Fixed a bug that resulted in redefined functions having the wrong source
+ file names in BASH_SOURCE.
+
+rr. Fixed a bug that caused the read builtin to assign null strings to variables
+ when using `read -N', which caused core dumps when referenced
+
+ss. Fixed a bug that caused `bash -m script' to not enable job control while
+ running the script.
+
+tt. Fixed a bug that caused `printf -v var' to dump core when used with the
+ %b format code.
+
+uu. Fixed a bug that caused the shell to exit with the wrong status if -e was
+ active and the shell exited on a substitution error.
+
+vv. Fixed a bug that caused the shell to seg fault if an array variable with
+ the same name as an existing associative array was implicitly created by
+ an assignment (declare a[n]=b).
+
+ww. Fixed a bug that caused a redirection to misbehave if the number specified
+ for a file descriptor overflows an intmax_t.
+
+xx. Fixed several bugs with the handling of valid and invalid unicode character
+ values when used with the \u and \U escape sequences to printf and $'...'.
+
+yy. Fixed a bug that caused tildes to not be escaped in expanded filenames,
+ making them subject to later expansion.
+
+zz. When using the pattern substitution word expansion, bash now runs the
+ replacement string through quote removal, since it allows quotes in that
+ string to act as escape characters. This is not backwards compatible, so
+ it can be disabled by setting the bash compatibility mode to 4.2.
+
+aaa. Fixed the rest of the cases where the shell runs non-allowed code in a
+ signal handler context.
+
+bbb. Fixed a bug that caused spurious DEL characters (\177) to appear in
+ double-quoted expansion where the RHS is evaluated to the empty string.
+
+ccc. Fixed a bug that caused the use of the shell's internal random number
+ generator for temporary file names to perturb the random number
+ sequence.
+
+ddd. Fixed several bugs that caused `declare -g' to not set the right global
+ variables or to misbehave when declaring global indexed arrays.
+
+eee. Fixed a logic bug that caused extended globbing in a multibyte locale to
+ cause failures when using the pattern substititution word expansions.
+
+fff. Fixed a bug that caused the `lastpipe' option to corrupt the file
+ descriptor used to read the script.
+
+ggg. Fixed a bug that causes the shell to delete DEL characters in the
+ expanded value of variables used in the same quoted string as variables
+ that expand to nothing.
+
+hhh. Fixed a bug that caused the shell to assign the wrong value from an
+ assignment like (( x=7 )) when `x' was an existing array variable.
+
+iii. Fixed a bug that caused the shell to misbehave when generating sequences
+ and the boundary values overflow an intmax_t.
+
+jjj. Fixed a bug caused expansion errors if an expansion of "$@" appeared
+ next to another expansion (e.g.. "${@}${x}").
+
+kkk. Fixed a potential buffer overflow bug when performing /dev/fd expansion.
+
+lll. Fixed a bug that resulted in an extra semicolon being added to compound
+ assignments when they were added to the history list.
+
+mmm. Fixed a bug that caused mapfile to read one extra line from the input.
+
+nnn. Fixed a bug that caused the mail checking code to use uninitialized
+ values.
+
+ooo. Fixed a bug that prevented history timestamps from being saved if the
+ history comment character is unset.
+
+ppp. Fixed a bug that caused the case-modifying expansions to not work with
+ multibyte characters.
+
+qqq. Fixed a bug that caused the edit-and-execute bindable readline command
+ to see the wrong data if invoked in the middle of a multi-line quoted
+ string.
+
+rrr. Fixed a bug that resulted in the shell returning the wrong exit status
+ for a background command on systems that recycle PIDs very quickly.
+
+sss. Fixed a bug that caused asynchronous group commands to not run any EXIT
+ trap defined in the body of the command.
+
+ttt. Fixed a bug that caused `eval "... ; return"' to not clean up properly.
+
+uuu. Fixed a bug that caused the shell to dump core if `read' reads an escaped
+ IFS whitespace character.
+
+vvv. Fixed a bug that caused BASH_COMMAND to be set to an incorrect value when
+ executing a (...) subshell.
+
+www. Fixed a couple of pointer aliasing bugs with the token string in arithmetic
+ evaluation.
+
+xxx. Fixed a bug with parsing multi-line command substitutions when reading
+ the `do' keyword followed by whitespace.
+
+yyy. Fixed a bug that caused the shell to seg fault if the time given to the
+ printf %(...)T format overflowed the value accepted by localtime(3).
+
+zzz. Fixed a problem with displaying help topics in two columns when the
+ translated text contained multibyte characters.
+
+aaaa. Fixed a bug with the extended globbing pattern matcher where a `*' was
+ followed by a negated extended glob pattern.
+
+bbbb. Fixed a race condition with short-lived coproc creation and reaping that
+ caused the child process to be reaped before the various coproc shell
+ variables were initialized.
+
+cccc. Fixed a bug where turning off `errexit' in command substitution subshells
+ was not reflected in $SHELLOPTS.
+
+dddd. Partially fixed an inconsistency in how the shell treated shell
+ functions run from an EXIT trap.
+
+eeee. Fixed a bug in how the shell invalidated FIFOs used for process
+ substitution when executing a pipeline (once rather than in every child).
+
+ffff. Fixed a bug that occurred when expanding a special variable ($@, $*)
+ within double quotes and the expansion resulted in an empty string.
+
+gggg. Fixed bugs with executing a SIGCHLD trap handler to make sure that it's
+ executed once per exited child.
+
+hhhh. Fixed a bug that caused `declare' and `test' to find variables that
+ had been given attributes but not assigned values. Such variables are
+ not set.
+
+iiii. Fixed a bug that caused commands in process substitutions to not look in
+ the local temporary environment when performing word expansions.
+
+jjjj. Fixed several problems with globstar expansions (**/**) returning null
+ filenames and multiple instances of the same pathname.
+
+kkkk. Fixed an oversight that did not allow the exit status of `coproc' to
+ be inverted using `!'.
+
+llll. Fixed a bug that caused the -e option to be re-enabled using `set -e'
+ even when executing in a context where -e is ignored.
+
+mmmm. Fixed a (mostly theoretical) bug with input lines longer than SIZE_MAX.
+
+nnnn. Fixed a bug that could result in double evaluation of command
+ substitutions when they appear in failed redirections.
+
+oooo. Fixed a bug that could cause seg faults during `mapfile' callbacks if
+ the callback unsets the array variable mapfile is using.
+
+pppp. Fixed several problems with variable assignments using ${var:=value}
+ when the variable assignment is supposed to have side effects.
+
+qqqq. Fixed a bug that caused a failure of an assignment statement preceding a
+ builtin caused the next invocation of a special builtin to exit the shell.
+
+rrrr. Fixed several problems with IFS when it appears in the temporary environment
+ and is used in redirections.
+
+ssss. Fixed a problem that caused IFS changes using ${IFS:=value} to modify
+ how preceding expansions were split.
+
+tttt. Fixed a problem that caused subshells to not run an EXIT trap they set.
+
+uuuu. Fixed a problem that caused shells started in posix mode to attempt to
+ import shell functions with invalid names from the environment. We now
+ print a warning.
+
+vvvv. Worked around a kernel problem that caused SIGCHLD to interrupt open(2)
+ on a FIFO used for process substitution, even if the SIGCHLD handler was
+ installed with the SA_RESTART flag.
+
+wwww. Fixed a problem that resulted in inconsistent expansion of $* and ${a[*]}.
+
+xxxx. Fixed a problem that caused `read -t' to crash when interrupted by
+ SIGINT.
+
+yyyy. Fixed a problem that caused pattern removal to fail randomly because the
+ pattern matcher read beyond the end of a string.
+
+zzzz. Fixed a bug that caused core dumps when shell functions tried to create
+ local shadow copies of special variables like GROUPS.
+
+aaaaa. Fixed a bug that caused SIGTERM to be occasionally lost by children of
+ interactive shells when it arrived before the child process reset the
+ handler from SIG_DFL.
+
+bbbbb. Fixed a bug that caused redirections like <&n- to leave file descriptor
+ n closed if executed with a builtin command.
+
+ccccc. Fixed a bug that caused incorrect completion quoting when completing a
+ word containing a globbing character with `show-all-if-ambiguous' set.
+
+ddddd. Fixed a bug that caused printf's %q format specifier not to quote a
+ tilde even if it appeared in a location where it would be subject to
+ tilde expansion.
+
+2. Changes to Readline
+
+a. Fixed a bug that did not allow the `dd', `cc', or `yy' vi editing mode
+ commands to work on the entire line.
+
+b. Fixed a bug that caused redisplay problems with prompts longer than 128
+ characters and history searches.
+
+c. Fixed a bug that caused readline to try and run code to modify its idea
+ of the screen size in a signal handler context upon receiving a SIGWINCH.
+
+d. Fixed a bug that caused the `meta' key to be enabled beyond the duration
+ of an individual call top readline().
+
+e. Added a workaround for a wcwidth bug in Mac OS X that caused readline's
+ redisplay to mishandle zero-width combining characters.
+
+f. Fixed a bug that caused readline to `forget' part of a key sequence when
+ a multiple-key sequence caused it to break out of an incremental search.
+
+g. Fixed bugs that caused readline to execute code in a signal handler
+ context if interrupted while reading from the file system during completion.
+
+h. Fixed a bug that caused readline to `forget' part of a key sequence when
+ reading an unbound multi-character key sequence.
+
+i. Fixed a bug that caused Readline's signal handlers to be installed beyond
+ the bounds of a single call to readline().
+
+j. Fixed a bug that caused the `.' command to not redo the most recent `R'
+ command in vi mode.
+
+k. Fixed a bug that caused ignoring case in completion matches to result in
+ readline using the wrong match.
+
+l. Paren matching now works in vi insert mode.
+
+m. Fix menu-completion to make show-all-if-ambiguous and menu-complete-display-prefix
+ work together.
+
+n. Fixed a bug that didn't allow the `cc', `dd', or `yy' commands to be redone
+ in vi editing mode.
+
+o. Fixed a bug that caused the filename comparison code to not compare
+ multibyte characters correctly when using case-sensitive or case-mapping
+ comparisons.
+
+p. Fixed the input reading loop to call the input hook function only when there
+ is no terminal input available.
+
+q. Fixed a bug that caused binding a macro to a multi-character key sequence
+ where the sequence and macro value share a common prefix to not perform
+ the macro replacement.
+
+r. Fixed several redisplay errors with multibyte characters and prompts
+ containing invisible characters when using horizontal scrolling.
+
+s. Fixed a bug that caused redisplay errors when trying to overwrite
+ existing characters using multibyte characters.
+
+3. New Features in Bash
+
+a. The `helptopic' completion action now maps to all the help topics, not just
+ the shell builtins.
+
+b. The `help' builtin no longer does prefix substring matching, so `help read'
+ does not match `readonly'.
+
+c. The shell can be compiled to not display a message about processes that
+ terminate due to SIGTERM.
+
+d. Non-interactive shells now react to the setting of checkwinsize and set
+ LINES and COLUMNS after a foreground job exits.
+
+e. There is a new shell option, `globasciiranges', which, when set to on,
+ forces globbing range comparisons to use character ordering as if they
+ were run in the C locale.
+
+f. There is a new shell option, `direxpand', which makes filename completion
+ expand variables in directory names in the way bash-4.1 did.
+
+g. In Posix mode, the `command' builtin does not change whether or not a
+ builtin it shadows is treated as an assignment builtin.
+
+h. The `return' and `exit' builtins accept negative exit status arguments.
+
+i. The word completion code checks whether or not a filename containing a
+ shell variable expands to a directory name and appends `/' to the word
+ as appropriate. The same code expands shell variables in command names
+ when performing command completion.
+
+j. In Posix mode, it is now an error to attempt to define a shell function
+ with the same name as a Posix special builtin.
+
+k. When compiled for strict Posix conformance, history expansion is disabled
+ by default.
+
+l. The history expansion character (!) does not cause history expansion when
+ followed by the closing quote in a double-quoted string.
+
+m. `complete' and its siblings compgen/compopt now takes a new `-o noquote'
+ option to inhibit quoting of the completions.
+
+n. Setting HISTSIZE to a value less than zero causes the history list to be
+ unlimited (setting it 0 zero disables the history list).
+
+o. Setting HISTFILESIZE to a value less than zero causes the history file size
+ to be unlimited (setting it to 0 causes the history file to be truncated
+ to zero size).
+
+p. The `read' builtin now skips NUL bytes in the input.
+
+q. There is a new `bind -X' option to print all key sequences bound to Unix
+ commands.
+
+r. When in Posix mode, `read' is interruptible by a trapped signal. After
+ running the trap handler, read returns 128+signal and throws away any
+ partially-read input.
+
+s. The command completion code skips whitespace and assignment statements
+ before looking for the command name word to be completed.
+
+t. The build process has a new mechanism for constructing separate help files
+ that better reflects the current set of compilation options.
+
+u. The -nt and -ot options to test now work with files with nanosecond
+ timestamp resolution.
+
+v. The shell saves the command history in any shell for which history is
+ enabled and HISTFILE is set, not just interactive shells.
+
+w. The shell has `nameref' variables and new -n(/+n) options to declare and
+ unset to use them, and a `test -R' option to test for them.
+
+x. The shell now allows assigning, referencing, and unsetting elements of
+ indexed arrays using negative subscripts (a[-1]=2, echo ${a[-1]}) which
+ count back from the last element of the array.
+
+y. The {x}<word redirection feature now allows words like {array[ind]} and
+ can use variables with special meanings to the shell (e.g., BASH_XTRACEFD).
+
+z. There is a new CHILD_MAX special shell variable; its value controls the
+ number of exited child statues the shell remembers.
+
+aa. There is a new configuration option (--enable-direxpand-default) that
+ causes the `direxpand' shell option to be enabled by default.
+
+bb. Bash does not do anything special to ensure that the file descriptor
+ assigned to X in {x}<foo remains open after the block containing it
+ completes.
+
+cc. The `wait' builtin has a new `-n' option to wait for the next child to
+ change status.
+
+dd. The `printf' %(...)T format specifier now uses the current time if no
+ argument is supplied.
+
+ee. There is a new variable, BASH_COMPAT, that controls the current shell
+ compatibility level.
+
+ff. The `popd' builtin now treats additional arguments as errors.
+
+gg. The brace expansion code now treats a failed sequence expansion as a
+ simple string and will continue to expand brace terms in the remainder
+ of the word.
+
+4. New Features in Readline
+
+a. Readline is now more responsive to SIGHUP and other fatal signals when
+ reading input from the terminal or performing word completion but no
+ longer attempts to run any not-allowable functions from a signal handler
+ context.
+
+b. There are new bindable commands to search the history for the string of
+ characters between the beginning of the line and the point
+ (history-substring-search-forward, history-substring-search-backward)
+
+c. Readline allows quoted strings as the values of variables when setting
+ them with `set'. As a side effect, trailing spaces and tabs are ignored
+ when setting a string variable's value.
+
+d. The history library creates a backup of the history file when writing it
+ and restores the backup on a write error.
+
+e. New application-settable variable: rl_filename_stat_hook: a function called
+ with a filename before using it in a call to stat(2). Bash uses it to
+ expand shell variables so things like $HOME/Downloads have a slash
+ appended.
+
+f. New bindable function `print-last-kbd-macro', prints the most-recently-
+ defined keyboard macro in a reusable format.
+
+g. New user-settable variable `colored-stats', enables use of colored text
+ to denote file types when displaying possible completions (colored analog
+ of visible-stats).
+
+h. New user-settable variable `keyseq-timout', acts as an inter-character
+ timeout when reading input or incremental search strings.
+
+i. New application-callable function: rl_clear_history. Clears the history list
+ and frees all readline-associated private data.
+
+j. New user-settable variable, show-mode-in-prompt, adds a characters to the
+ beginning of the prompt indicating the current editing mode.
+
+k. New application-settable variable: rl_input_available_hook; function to be
+ called when readline needs to check whether there is data available on its
+ input source. The default hook checks rl_instream.
+
+l. Readline calls an application-set event hook (rl_signal_event_hook) after
+ it gets a signal while reading input (read returns -1/EINTR but readline
+ does not handle the signal immediately) to allow the application to handle
+ or otherwise note it. Not currently called for SIGHUP or SIGTERM.
+
+m. If the user-settable variable `history-size' is set to a value less than
+ 0, the history list size is unlimited.
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-4.2-release,
+and the previous version, bash-4.2-rc2.
+
+1. Changes to Bash
+
+a. Fixed a bug that caused some variables to be clobbered by a longjmp,
+ resulting in stack corruption.
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-4.2-rc2,
+and the previous version, bash-4.2-rc1.
+
+1. Changes to Bash
+
+a. Changes to bash_directory_completion_hook so that it's assigned to the
+ readline rl_directory_rewrite_hook variable, which modifies the directory
+ name passed to opendir without modifying the directory name the user
+ typed.
+
+b. Fixed bug in select builtin that caused it to not terminate correctly if
+ the read timed out due to $TMOUT.
+
+c. Fixed a problem that resulted in non-repeatable sequences of random
+ numbers when RANDOM=0.
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-4.2-rc1,
+and the previous version, bash-4.2-beta.
+
+1. Changes to Bash
+
+a. Fixed a bug that caused some redirection errors to leak file descriptors.
+
+b. Fixed a bug that caused unary `+' and `-' arithmetic operators to have a
+ higher precedence than unary `!' and `~'.
+
+c. Fixed a bug that caused simple commands in a pipeline to affect the exit
+ status ($?) seen by subsequent pipeline commands.
+
+d. A number of cygwin-specific changes to avoid the use of text-mode files
+ and file access, and to make sure that \r is handled correctly.
+
+e. Fixed a bug that caused the read builtin to not return failure if an
+ attempt is made to assign to a readonly variable.
+
+f. Fixed a bug that caused some builtin usage messages to not be translated.
+
+g. Fixed a bug that caused the getopts builtin to not return failure if an
+ attempt is made to assign to a readonly variable. Now it returns 2.
+
+h. Fixed the cd and pwd builtins to return failure if PWD is readonly and
+ cannot be assigned to.
+
+i. Added code to check the return value of access(2) on Solaris systems,
+ since it returns success for executable tests (e.g., `test -x') when
+ run by root, even if the file permissions don't allow execution.
+
+2. Changes to Readline
+
+a. Fixed a bug that caused directory names in words to be completed to not
+ be dequoted correctly.
+
+3. New Features in Bash
+
+4. New Features in Readline
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-4.2-beta,
+and the previous version, bash-4.2-alpha.
+
+1. Changes to Bash
+
+a. Fixed a bug that caused the \W prompt string escape to not add a closing
+ NULL.
+
+b. Fixed a bug that caused partially-quoted words that were not subject to
+ word splitting to retained quoted NULLs.
+
+c. Added considerable efficiency speedups when pattern matching in multibyte
+ locales by skipping multibyte character functions where possible.
+
+d. Added considerable speedups to variable expansion when in multibyte locales.
+
+e. Fixed a bug that caused the expansion of $* when there are no positional
+ parameters to cause the shell to dump core when used in a pattern
+ matching context.
+
+f. Fixed a bug that caused variable expansions preceding regular builtins to
+ not change the shell environment during their execution.
+
+2. Changes to Readline
+
+a. Fixed a bug that made an explicit argument of 0 to yank-last-arg behave
+ as if it were a negative argument.
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-4.2-alpha,
+and the previous version, bash-4.1-release.
+
+1. Changes to Bash
+
+a. Fixed a bug in the parser when processing alias expansions containing
+ quoted newlines.
+
+b. Fixed a memory leak in associative array expansion.
+
+c. Fixed a bug that caused quoted here-strings to be requoted when printed.
+
+d. Fixed a bug in arithmetic expansion that caused the index in an array
+ expansion to be evaluated twice under certain circumstances.
+
+e. Fixed several bugs with the expansion and display of variables that have
+ been given attributes but not values and are technically unset.
+
+f. Fixed a bug that caused core dumps when using filename completion that
+ expands to a filename containing a globbing character.
+
+g. Fixed a bug that caused assignment statements preceding a special builtin
+ when running in Posix mode to not persist after the builtin completed
+ when the special builtin was executed in a shell function without any
+ local variables.
+
+h. Fixed a bug that caused a command to remain in the hash table even after
+ `hash command' did not find anything if there was already an existing
+ hashed pathname.
+
+i. Fixed several bugs caused by executing unsafe functions from a signal
+ handler in the cases where a signal handler is executed immediately
+ rather than setting a flag for later execution.
+
+j. Fixed a bug that caused some internal flag variables to be set
+ incorrectly if `read -t' timed out.
+
+k. Fixed a Posix compatibility issue by making sure that a backslash escaping
+ a `}' within a double-quoted ${...} parameter expansion is removed as part
+ of the parameter expansion.
+
+l. Fixed a bug that caused execution of a trap to overwrite PIPESTATUS.
+
+m. Fixed a bug that caused here documents to not be displayed correctly
+ when attached to commands inside compound commands.
+
+n. Fixed a bug that caused the printf builtin to use the wrong precision
+ when using the `*' modifier.
+
+o. Fixed a bug that caused an arriving SIGCHLD to interrupt output functions
+ like those invoked by echo or printf.
+
+p. Changed to use a more robust mechanism than eaccess(2) when test is
+ checking filenames for execution permission.
+
+q. Fixed a bug that caused spurious semicolons to be added into the command
+ history in certain cases.
+
+r. Fixed a bug that caused the shell to free non-allocated memory when
+ unsetting element 0 of an associative array after it was assigned
+ implicitly.
+
+s. Fixed a bug that could cause the shell to dump core if using the `v'
+ vi editing command on a multi-line command.
+
+t. Fixed a bug that left FIFOs opened by process substitutions open long
+ enough to potentially cause file descriptor exhaustion when running a
+ shell function or shell builtin.
+
+u. Fixed a bug that caused the history expansion functions to not recognize
+ process substitution or extended glob patterns as single words.
+
+v. Fixed a bug that caused restricted shells to set a restricted command's
+ exit status incorrectly.
+
+w. Fixed a bug that caused bash to ignore the wrong set of filenames when
+ completing a command using the `complete-filename' readline command.
+
+x. Fixed a bug that caused a -PID argument following a -s sig or -n sig to
+ not be interpreted as a signal specification.
+
+y. Changed posix-mode behavior of a parse error in a `.' script or `eval'
+ command to exit the shell under Posix-specified conditions. Previous
+ versions printed a warning.
+
+z. Fixed a bug in \W prompt expansion that resulted in incorrect expansion
+ in the event of overlapping strings.
+
+aa. Fixed a bug that caused the := parameter expansion operator to return the
+ wrong value as the result of the expansion.
+
+bb. When in Posix mode, a single quote is not treated specially in a
+ double-quoted ${...} expansion, unless the expansion operator is
+ # or % or the non-Posix `//', `^', and `,'. In particular, it does
+ not define a new quoting context. This is from Posix interpretation 221.
+
+cc. Fixed a bug that inadvertently allowed program names containing slashes
+ to be entered into the command hash table.
+
+dd. Fixed a bug that caused the select builtin to incorrectly compute the
+ display width of the arguments in the presence of multibyte characters.
+
+ee. Fixed a bug that caused bash to not change the xtrace file descriptor if
+ BASH_XTRACEFD was found in the shell environment at startup.
+
+ff. Fixed a memory leak in the pattern removal parameter expansion.
+
+gg. Fixed a bug that caused SIGINT to fail to interrupt a nested loop if the
+ loop was in a pipeline.
+
+hh. Fixed a problem in $(...) parsing that caused the parser to add an extra
+ space to a here-document delimiter if the first word contained a `/'.
+
+ii. Fixed a bug that caused functions defined with the `function' reserved
+ word to require braces around the function body.
+
+jj. Fixed a bug that caused bash to dump core when a variable expansion being
+ used as an array subscript failed.
+
+kk. Fixed a bug that caused bash to dump core if the case-modification
+ expansions were used on a variable with a null value.
+
+ll. Fixed a bug that caused partially-quoted strings to be split incorrectly
+ if a variable with a null value was expanded within double quotes.
+
+mm. The pattern substitution word expansion has been sped up dramatically
+ when running in a locale with multibyte characters.
+
+nn. Fixed a bug that caused history -a to not write the correct lines to
+ the history file if all the new lines in the history list were added
+ since the last time the history file was read or written.
+
+oo. Fixed a bug that caused completion of a word with an unclosed `` command
+ substitution to set the prompt incorrectly.
+
+pp. Fixed a bug that caused extended globbing patterns in $HISTIGNORE or
+ $GLOBIGNORE to be incorrectly scanned.
+
+qq. Fixed a bug caused by closing file descriptors 3-20 on shell startup. The
+ shell now sets them to close-on-exec.
+
+rr. Fixed a bug that caused the exit status of `exec file' to be set incorrectly
+ if `file' was a directory.
+
+ss. Fixed a bug in the `.' builtin to make a non-interactive posix-mode shell
+ exit if the file argument to `.' is not found. Prefixing exec with
+ `command' makes the shell not exit. Posix requires this behavior.
+
+tt. Fixed a bug that caused `sh -c 'command exec; exit 1' to hang.
+
+uu. Fixed a bug in $(...) command substitution parsing that caused the shell
+ to treat backslash-newline incorrectly when parsing a comment.
+
+vv. Fixed bug that caused brace expansion sequence generation to misbehave
+ when supplied integers greater than 2**31 - 1.
+
+ww. Fixed a bug that caused failure to save file descriptors for redirections
+ to corrupt shell file descriptors.
+
+xx. Fixed a bug that caused bash-forward-shellword to not correctly handle
+ quoted strings.
+
+2. Changes to Readline
+
+a. Fixed a bug that caused the unconverted filename to be added to the list of
+ completions when the application specified filename conversion functions.
+
+b. Fixed a bug that caused the wrong filename to be passed to opendir when the
+ application has specified a filename dequoting function.
+
+c. Fixed a bug when repeating a character search in vi mode in the case where
+ there was no search to repeat.
+
+d. When show-all-if-ambiguous is set, the completion routines no longer insert
+ a common match prefix that is shorter than the text being completed.
+
+e. The full set of vi editing commands may now be used in callback mode.
+
+f. Fixed a bug that caused readline to not update its idea of the terminal
+ dimensions while running in `no-echo' mode.
+
+h. Fixed a bug that caused readline to dump core if an application called
+ rl_prep_terminal without setting rl_instream.
+
+i. Fixed a bug that caused meta-prefixed characters bound to incremental
+ search forward or backward to not be recognized if they were typed
+ subsequently.
+
+j. The incremental search code treats key sequences that map to the same
+ functions as (default) ^G, ^W, and ^Y as equivalent to those characters.
+
+k. Fixed a bug in menu-complete that caused it to misbehave with large
+ negative argument.
+
+l. Fixed a bug that caused vi-mode yank-last-arg to ring the bell when invoked
+ at the end of the line.
+
+3. New Features in Bash
+
+a. `exec -a foo' now sets $0 to `foo' in an executable shell script without a
+ leading #!.
+
+b. Subshells begun to execute command substitutions or run shell functions or
+ builtins in subshells do not reset trap strings until a new trap is
+ specified. This allows $(trap) to display the caller's traps and the
+ trap strings to persist until a new trap is set.
+
+c. `trap -p' will now show signals ignored at shell startup, though their
+ disposition still cannot be modified.
+
+d. $'...', echo, and printf understand \uXXXX and \UXXXXXXXX escape sequences.
+
+e. declare/typeset has a new `-g' option, which creates variables in the
+ global scope even when run in a shell function.
+
+f. test/[/[[ have a new -v variable unary operator, which returns success if
+ `variable' has been set.
+
+g. Posix parsing changes to allow `! time command' and multiple consecutive
+ instances of `!' (which toggle) and `time' (which have no cumulative
+ effect).
+
+h. Posix change to allow `time' as a command by itself to print the elapsed
+ user, system, and real times for the shell and its children.
+
+j. $((...)) is always parsed as an arithmetic expansion first, instead of as
+ a potential nested command substitution, as Posix requires.
+
+k. A new FUNCNEST variable to allow the user to control the maximum shell
+ function nesting (recursive execution) level.
+
+l. The mapfile builtin now supplies a third argument to the callback command:
+ the line about to be assigned to the supplied array index.
+
+m. The printf builtin has a new %(fmt)T specifier, which allows time values
+ to use strftime-like formatting.
+
+n. There is a new `compat41' shell option.
+
+o. The cd builtin has a new Posix-mandated `-e' option.
+
+p. Negative subscripts to indexed arrays, previously errors, now are treated
+ as offsets from the maximum assigned index + 1.
+
+q. Negative length specifications in the ${var:offset:length} expansion,
+ previously errors, are now treated as offsets from the end of the variable.
+
+r. Parsing change to allow `time -p --'.
+
+s. Posix-mode parsing change to not recognize `time' as a keyword if the
+ following token begins with a `-'. This means no more Posix-mode
+ `time -p'. Posix interpretation 267.
+
+t. There is a new `lastpipe' shell option that runs the last command of a
+ pipeline in the current shell context. The lastpipe option has no
+ effect if job control is enabled.
+
+u. History expansion no longer expands the `$!' variable expansion.
+
+v. Posix mode shells no longer exit if a variable assignment error occurs
+ with an assignment preceding a command that is not a special builtin.
+
+w. Non-interactive mode shells exit if -u is enabled and an attempt is made
+ to use an unset variable with the % or # expansions, the `//', `^', or
+ `,' expansions, or the parameter length expansion.
+
+x. Posix-mode shells use the argument passed to `.' as-is if a $PATH search
+ fails, effectively searching the current directory. Posix-2008 change.
+
+4. New Features in Readline
+
+a. The history library does not try to write the history filename in the
+ current directory if $HOME is unset. This closes a potential security
+ problem if the application does not specify a history filename.
+
+b. New bindable variable `completion-display-width' to set the number of
+ columns used when displaying completions.
+
+c. New bindable variable `completion-case-map' to cause case-insensitive
+ completion to treat `-' and `_' as identical.
+
+d. There are new bindable vi-mode command names to avoid readline's case-
+ insensitive matching not allowing them to be bound separately.
+
+e. New bindable variable `menu-complete-display-prefix' causes the menu
+ completion code to display the common prefix of the possible completions
+ before cycling through the list, instead of after.
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-4.1-rc,
+and the previous version, bash-4.1-beta.
+
+1. Changes to Bash
+
+a. Fixed a bug that caused printf to not return a partial value when it
+ encountered an error while converting an integer argument.
+
+b. Fixed a bug that caused setting one of the compatNN options to not
+ turn off the others.
+
+c. The (undocumented) --wordexp option is no longer included by default.
+
+d. Fixed a bug in conditional command execution that caused it to not
+ correctly ignore the exit status under certain circumstances.
+
+e. Added a configure-time check for correctly-working asprintf/snprintf.
+
+f. Fixed some problems with line number calculation and display when sourcing
+ a file in an interactive shell.
+
+g. Fixed a bug that caused the shell to crash when using `declare -A foo=bar'.
+
+h. Fixed a bug that caused an off-by-one error when calculating the directories
+ to display with the PROMPT_DIRTRIM option.
+
+2. Changes to Readline
+
+a. Fixed a bug that caused applications using the callback interface to not
+ react to SIGINT (or other signals) until another character arrived.
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-4.1-beta,
+and the previous version, bash-4.1-alpha.
+
+1. Changes to Bash
+
+a. Fixed a bug in mapfile that caused the shell to crash if it was passed the
+ name of an associative array.
+
+b. Fixed a bug that caused the shell to incorrectly split case patterns if
+ they contained characters in $IFS.
+
+c. Fixed a bug that caused the shell to set $? to the wrong value when using
+ a construct ending with a variable assignment with set -x enabled and PS4
+ containing a command substitution.
+
+d. Fixed a bug that caused the shell to read commands incorrectly if an
+ expansion error occurred under certain conditions in a user-specified
+ subshell.
+
+e. Fixed a bug that caused the shell to set $? incorrectly if a parse error
+ occurred in an evaluation context ("eval", trap command, dot script, etc.)
+
+f. Fixed a bug that caused the shell to attempt command substitution
+ completion within a single-quoted string.
+
+g. Fixed a bug that caused the shell to insert an extra single quote during
+ word completion.
+
+h. Fixed a bug that caused the shell to crash if invoked with the environment
+ variable EMACS having a null value.
+
+i. Fixed a bug that caused bash to incorrectly report the presence of new
+ mail in a `maildir' environment.
+
+j. Fixed a bug that caused the shell to not recognize a here-document ending
+ delimiter inside a command substitution.
+
+k. Fixed a bug that caused the shell to crash when a a dynamic array variable
+ was assigned a scalar value.
+
+2. Changes to Readline
+
+3. New Features in Bash
+
+a. The mapfile/readarray builtin no longer stores the commands it invokes via
+ callbacks in the history list.
+
+b. There is a new `compat40' shopt option.
+
+c. The < and > operators to [[ do string comparisons using the current locale
+ only if the compatibility level is greater than 40 (set to 41 by default).
+
+4. New Features in Readline
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-4.1-alpha,
+and the previous version, bash-4.0-release.
+
+1. Changes to Bash
+
+a. Fixed bugs in the parser involving new parsing of the commands contained
+ in command substitution when the substitution is read.
+
+b. Fixed a bug that caused the shell to dump core when performing programmable
+ completion using a shell function.
+
+c. Fixed a bug in `mapfile' that caused it to invoke callbacks at the wrong
+ time.
+
+d. Fixed a bug that caused the shell to dump core when listing jobs in the
+ `exit' builtin.
+
+e. Fixed several bugs encountered when reading subscripts in associative
+ array assignments and expansions.
+
+f. Fixed a bug that under some circumstances caused an associative array to
+ be converted to an indexed array.
+
+g. Fixed a bug that caused syntax errors and SIGINT interrupts to not set
+ $? to a value > 128.
+
+h. Fixed a bug that caused the shell to remove FIFOs associated with process
+ substitution inside shell functions.
+
+i. Fixed a bug that caused terminal attributes to not be reset when the
+ `read' builtin timed out.
+
+j. Fixed a bug in brace expansion that caused unwanted zero padding of the
+ expanded terms.
+
+k. Fixed a bug that prevented the |& construct from working as intended when
+ used with a simple command with additional redirections.
+
+l. Fixed a bug with the case statment ;& terminator that caused the shell to
+ dereference a NULL pointer.
+
+m. Fixed a bug that caused assignment statements or redirections preceding
+ a simple command name to inhibit alias expansion.
+
+n. Fixed the behavior of `set -u' to conform to the latest Posix interpretation:
+ every expansion of an unset variable except $@ and $* will cause the
+ shell to exit.
+
+o. Fixed a bug that caused double-quoted expansions of $* inside word
+ expansions like ${x#$*} to not expand properly when $IFS is empty.
+
+p. Fixed a bug that caused traps to set $LINENO to the wrong value when they
+ execute.
+
+q. Fixed a bug that caused off-by-one errors when computing history lines in
+ the `fc' builtin.
+
+r. Fixed a bug that caused some terminating signals to not exit the shell
+ quickly enough, forcing the kernel to send the signal (e.g., SIGSEGV)
+ multiple times.
+
+s. Fixed a bug that caused the shell to attempt to add empty lines to the
+ history list when reading here documents.
+
+t. Made some internal changes that dramatically speeds up sequential indexed
+ array access.
+
+u. Fixed a bug that caused the shell to write past the end of a string when
+ completing a double-quoted string ending in a backslash.
+
+v. Fixed a bug that caused the shell to replace too many characters when a
+ pattern match was null in a ${foo//bar} expansion.
+
+w. Fixed bugs in the expansion of ** that caused duplicate directory names
+ and the contents of the current directory to be omitted.
+
+x. Fixed a bug that caused $? to not be set correctly when referencing an
+ unset variable with set -u and set -e enabled.
+
+y. Fixed a bug caused by executing an external program from the DEBUG trap
+ while a pipeline was running. The effect was to disturb the pipeline
+ state, occasionally causing it to hang.
+
+z. Fixed a bug that caused the ** glob expansion to dump core if it
+ encountered an unsearchable directory.
+
+aa. Fixed a bug that caused `command -v' and `command -V' to not honor the
+ path set by the -p option.
+
+bb. Fixed a bug that caused brace expansion to take place too soon in some
+ compound array assignments.
+
+cc. Fixed a bug that caused programmable completion functions' changes to
+ READLINE_POINT to not be reflected back to readline.
+
+dd. Fixed a bug that caused the shell to dump core if a trap was executed
+ during a shell assignment statement.
+
+ee. Fixed an off-by-one error when computing the number of positional
+ parameters for the ${@:0:n} expansion.
+
+ff. Fixed a problem with setting COMP_CWORD for programmable completion
+ functions that could leave it set to -1.
+
+gg. Fixed a bug that caused the ERR trap to be triggered in some cases where
+ `set -e' would not have caused the shell to exit.
+
+hh. Fixed a bug that caused changes made by `compopt' to not persist past the
+ completion function in which compopt was executed.
+
+ii. Fixed a bug that caused the list of hostname completions to not be cleared
+ when HOSTNAME was unset.
+
+jj. Fixed a bug that caused variable expansion in here documents to look in
+ any temporary environment.
+
+kk. Bash and readline can now convert file names between precomposed and
+ decomposed Unicode on Mac OS X ("keyboard" and file system forms,
+ respectively). This affects filename completion (using new
+ rl_filename_rewrite_hook), globbing, and readline redisplay.
+
+ll. The ERR and EXIT traps now see a non-zero value for $? when a parser
+ error after set -e has been enabled causes the shell to exit.
+
+mm. Fixed a bug that in brace expansion that caused zero-prefixed terms to
+ not contain the correct number of digits.
+
+nn. Fixed a bug that caused the shell to free non-allocated memory when
+ unsetting an associative array which had had a value implicitly assigned
+ to index "0".
+
+oo. Fixed a memory leak in the ${!prefix@} expansion.
+
+pp. Fixed a bug that caused printf to not correctly report all write errors.
+
+qq. Fixed a bug that caused single and double quotes to act as delimiters
+ when splitting a command line into words for programmable completion.
+
+rr. Fixed a bug that caused ** globbing that caused **/path/* to match every
+ directory, not just those matching `path'.
+
+ss. Fixed a bug that caused the shell to dump core when running `help' without
+ arguments if the terminal width was fewer than 7 characters.
+
+2. Changes to Readline
+
+a. The SIGWINCH signal handler now avoids calling the redisplay code if
+ one arrives while in the middle of redisplay.
+
+b. Changes to the timeout code to make sure that timeout values greater
+ than one second are handled better.
+
+c. Fixed a bug in the redisplay code that was triggered by a prompt
+ containing invisible characters exactly the width of the screen.
+
+d. Fixed a bug in the redisplay code encountered when running in horizontal
+ scroll mode.
+
+e. Fixed a bug that prevented menu completion from properly completing
+ filenames.
+
+f. Fixed a redisplay bug caused by a multibyte character causing a line to
+ wrap.
+
+g. Fixed a bug that caused key sequences of two characters to not be
+ recognized when a longer sequence identical in the first two characters
+ was bound.
+
+h. Fixed a bug that caused history expansion to be attempted on $'...'
+ single-quoted strings.
+
+i. Fixed a bug that caused incorrect redisplay when the prompt contained
+ multibyte characters in an `invisible' sequence bracketed by \[ and
+ \].
+
+j. Fixed a bug that caused history expansion to short-circuit after
+ encountering a multibyte character.
+
+3. New Features in Bash
+
+a. Here-documents within $(...) command substitutions may once more be
+ delimited by the closing right paren, instead of requiring a newline.
+
+b. Bash's file status checks (executable, readable, etc.) now take file
+ system ACLs into account on file systems that support them.
+
+c. Bash now passes environment variables with names that are not valid
+ shell variable names through into the environment passed to child
+ processes.
+
+d. The `execute-unix-command' readline function now attempts to clear and
+ reuse the current line rather than move to a new one after the command
+ executes.
+
+e. `printf -v' can now assign values to array indices.
+
+f. New `complete -E' and `compopt -E' options that work on the "empty"
+ completion: completion attempted on an empty command line.
+
+g. New complete/compgen/compopt -D option to define a `default' completion:
+ a completion to be invoked on command for which no completion has been
+ defined. If this function returns 124, programmable completion is
+ attempted again, allowing a user to dynamically build a set of completions
+ as completion is attempted by having the default completion function
+ install individual completion functions each time it is invoked.
+
+h. When displaying associative arrays, subscripts are now quoted.
+
+i. Changes to dabbrev-expand to make it more `emacs-like': no space appended
+ after matches, completions are not sorted, and most recent history entries
+ are presented first.
+
+j. The [[ and (( commands are now subject to the setting of `set -e' and the
+ ERR trap.
+
+k. The source/. builtin now removes NUL bytes from the file before attempting
+ to parse commands.
+
+l. There is a new configuration option (in config-top.h) that forces bash to
+ forward all history entries to syslog.
+
+m. A new variable $BASHOPTS to export shell options settable using `shopt' to
+ child processes.
+
+n. There is a new confgure option that forces the extglob option to be
+ enabled by default.
+
+o. New variable $BASH_XTRACEFD; when set to an integer bash will write xtrace
+ output to that file descriptor.
+
+p. If the optional left-hand-side of a redirection is of the form {var}, the
+ shell assigns the file descriptor used to $var or uses $var as the file
+ descriptor to move or close, depending on the redirection operator.
+
+q. The < and > operators to the [[ conditional command now do string
+ comparison according to the current locale.
+
+r. Programmable completion now uses the completion for `b' instead of `a'
+ when completion is attempted on a line like: a $(b c.
+
+s. Force extglob on temporarily when parsing the pattern argument to
+ the == and != operators to the [[ command, for compatibility.
+
+t. Changed the behavior of interrupting the wait builtin when a SIGCHLD is
+ received and a trap on SIGCHLD is set to be Posix-mode only.
+
+u. The read builtin has a new `-N nchars' option, which reads exactly NCHARS
+ characters, ignoring delimiters like newline.
+
+4. New Features in Readline
+
+a. New bindable function: menu-complete-backward.
+
+b. In the vi insertion keymap, C-n is now bound to menu-complete by default,
+ and C-p to menu-complete-backward.
+
+c. When in vi command mode, repeatedly hitting ESC now does nothing, even
+ when ESC introduces a bound key sequence. This is closer to how
+ historical vi behaves.
+
+d. New bindable function: skip-csi-sequence. Can be used as a default to
+ consume key sequences generated by keys like Home and End without having
+ to bind all keys.
+
+e. New application-settable function: rl_filename_rewrite_hook. Can be used
+ to rewite or modify filenames read from the file system before they are
+ compared to the word to be completed.
+
+f. New bindable variable: skip-completed-text, active when completing in the
+ middle of a word. If enabled, it means that characters in the completion
+ that match characters in the remainder of the word are "skipped" rather
+ than inserted into the line.
+
+g. The pre-readline-6.0 version of menu completion is available as
+ "old-menu-complete" for users who do not like the readline-6.0 version.
+
+h. New bindable variable: echo-control-characters. If enabled, and the
+ tty ECHOCTL bit is set, controls the echoing of characters corresponding
+ to keyboard-generated signals.
+
+i. New bindable variable: enable-meta-key. Controls whether or not readline
+ sends the smm/rmm sequences if the terminal indicates it has a meta key
+ that enables eight-bit characters.
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-4.0-release,
+and the previous version, bash-4.0-rc1.
+
+1. Changes to Bash
+
+a. Changed the message printed when setlocale(3) fails to only include the
+ strerror error text if the call changes errno.
+
+b. Changed trap command execution to reset the line number before running a
+ trap (except DEBUG and RETURN traps).
+
+c. Fixed behavior of case-modifiying word expansions to not work on
+ individual words within a variable's value.
+
+d. Fixed a bug that caused mapfile to not be interruptible when run in an
+ interactive shell.
+
+e. Fixed a bug that caused mapfile to not run callbacks for the first line
+ read.
+
+f. Fixed a bug that caused mapfile to not honor EOF typed in an interactive
+ shell.
+
+g. Fixed the coprocess reaping code to not run straight from a signal handler.
+
+h. Fixed a bug that caused printf -b to ignore the first % conversion specifier
+ in the format string on 64-bit systems.
+
+i. Fixed a bug that caused incorrect word splitting when `:', `=', or `~'
+ appeared in $IFS.
+
+j. Fixed a bug that caused data corruption in the programmable completion code
+ when a shell function called from a completion aborted execution.
+
+k. Fixed a bug that caused the CPU usage reported by the `time' builtin to be
+ capped at 100%.
+
+l. Changed behavior of shell when -e option is in effect to reflect consensus
+ of Posix shell standardization working group.
+
+m. Fixed a bug introduced in bash-4.0-alpha that caused redirections to not
+ be displayed by `type' or `declare' when appearing in functions under
+ certain circumstances.
+
+2. Changes to Readline
+
+a. Fixed a bug that caused !(...) extended glob patterns to inhibit later
+ history expansion.
+
+b. Reworked the signal handling to avoid calling disallowed functions from a
+ signal handler.
+
+3. New Features in Bash
+
+a. `readarray' is now a synonym for `mapfile'.
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-4.0-rc1,
+and the previous version, bash-4.0-beta2.
+
+1. Changes to Bash
+
+a. Fixed a bug that caused parsing errors when a $()-style command
+ substitution was follwed immediately by a quoted newline.
+
+b. Fixed a bug that caused extended shell globbing patterns beginning with
+ `*(' to not work when used with pattern substitution word expansions.
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-4.0-beta2,
+and the previous version, bash-4.0-beta.
+
+1. Changes to Bash
+
+a. Fixed a bug that caused failed word expansions to set $? but not
+ PIPESTATUS.
+
+b. Changed filename completion to quote the tilde in a filename with a
+ leading tilde that exists in the current directory.
+
+c. Fixed a bug that caused a file descriptor leak when performing
+ redirections attached to a compound command.
+
+d. Fixed a bug that caused expansions of $@ and $* to not exit the shell if
+ the -u option was enabled and there were no posititional parameters.
+
+e. Fixed a bug that resulted in bash not terminating immediately if a
+ terminating signal was received while performing output.
+
+f. Fixed a bug that caused the shell to crash after creating 256 process
+ substitutions during word completion.
+
+2. Changes to Readline
+
+a. Fixed a bug that caused redisplay errors when using prompts with invisible
+ characters and numeric arguments to a command in a multibyte locale.
+
+b. Fixed a bug that caused redisplay errors when using prompts with invisible
+ characters spanning more than two physical screen lines.
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-4.0-beta,
+and the previous version, bash-4.0-alpha.
+
+1. Changes to Bash
+
+a. Fixed a typo that caused a variable to be used before initialization
+ while parsing Posix-style command substitutions.
+
+b. Fixed a bug that caused stray ^? when the expansion of a parameter used
+ as part of a pattern removal expansion is empty, but part of a non-
+ empty string.
+
+c. Fixed a bug that could cause strings not converted to numbers by strtol
+ to be treated as if the conversion had been successful.
+
+d. The `return' builtin now accepts no options and requires a `--' before
+ a negative return value, as Posix requires.
+
+e. Fixed a bug that caused local variables to be created with the empty
+ string for a value rather than no value.
+
+f. Changed behavior so the shell now acts as if it received an interrupt
+ when a pipeline is killed by SIGINT while executing a list.
+
+g. Fixed a bug that caused `declare var' and `typeset var' to initialize
+ `var' to the empty string.
+
+h. Changed `bind' builtin to print a warning but proceed if invoked when
+ line editing is not active.
+
+i. Fixed a bug that caused the shell to exit when the `errexit' option is
+ set and a command in a pipeline returns a non-zero exit status.
+
+j. Fixed a bug that caused the shell to not run the exit trap in a command
+ run with `bash -c' under some circumstances.
+
+k. Fixed a bug that caused parser errors to occasionally not set $? when
+ running commands with `eval'.
+
+l. Fixed a bug that caused stray control characters when evaluating compound
+ array assignments containing $'\x7f' escapes.
+
+m. Fixed a bug that caused redirections involving file descriptor 10 as the
+ target to behave incorrectly.
+
+n. Fixed a bug that could cause memory to be freed multiple times when
+ assigning to COMP_WORDBREAKS.
+
+o. Fixed a bug that could cause NULL pointer dereferences when COMP_WORDBREAKS
+ was unset.
+
+2. Changes to Readline
+
+3. New Features in Bash
+
+a. A value of 0 for the -t option to `read' now returns success if there is
+ input available to be read from the specified file descriptor.
+
+b. CDPATH and GLOBIGNORE are ignored when the shell is running in privileged
+ mode.
+
+c. New bindable readline functions shell-forward-word and shell-backward-word,
+ which move forward and backward words delimited by shell metacharacters
+ and honor shell quoting.
+
+d. New bindable readline functions shell-backward-kill-word and shell-kill-word
+ which kill words backward and forward, but use the same word boundaries
+ as shell-forward-word and shell-backward-word.
+
+4. New Features in Readline
+
+a. If the kernel supports it, readline displays special characters
+ corresponding to a keyboard-generated signal when the signal is received.
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-4.0-alpha,
+and the previous version, bash-3.2-release.
+
+1. Changes to Bash
+
+a. Fixed several bugs in old-style `` command substitution parsing, including
+ comment parsing and quoted string handling.
+
+b. Fixed problems parsing arguments to the [[ command's =~ regular expression
+ matching operator: metacharacter and whitespace parsing.
+
+c. Fixed a bug that caused the shell to inappropriately reuse high-numbered
+ file descriptors it used internally.
+
+d. Fixed a bug in pattern replacement word expansions that caused a `/' as
+ the first character of an expanded pattern to be mistaken for a global
+ replacement specifier.
+
+e. Fixed several problems with the asprintf and snprintf replacement functions
+ that caused hangs and crashes.
+
+f. Fixed a bug in the calculation of the current and previous job that caused
+ it to refer to incorrect jobs.
+
+g. Fixed a bug in the check for the validity of a hashed command pathname that
+ caused unnecessary hash table deletions and additions.
+
+h. Fixed a bug that caused child processes to inherit the wrong value for $!.
+
+i. Fixed a bug that caused `.' to fail to read and execute commands from non-
+ regular files such as devices or named pipes.
+
+j. Fixed a bug in printf formatting for the %x and %X expansions that occurred
+ on some systems.
+
+k. Fixed a bug that caused the shell to crash when creating temporary files if
+ $TMPDIR named a non-writable directory.
+
+l. Fixed a bug that caused the shell to ignore $TMPDIR when creating temporary
+ files under some circumstances.
+
+m. Fixed a bug that caused named pipes created by process substitution to not
+ be cleaned up.
+
+n. Fixed a bug that caused HISTTIMEFORMAT to not be honored when it appeared
+ in the initial shell environment.
+
+o. Fixed several bugs in the expansion of $* and $@ (quoted and unquoted)
+ when IFS is null or contains non-whitespace characters; the same changes
+ apply to arrays subscripted with * or @.
+
+p. Fixed several problems with pattern substitution expansions on the
+ positional parameters and arrays subscripted with * or @ that occurred
+ when $IFS was set to the empty string.
+
+q. Made a change to the default locale initialization code that should
+ result in better behavior from the locale-aware library functions.
+
+r. Fixed a bug that caused compacting the jobs list to drop jobs.
+
+s. Fixed a bug that caused jumps back to the top-level processing loop from
+ a builtin command to leave the shell in an inconsistent state.
+
+t. Fixed a bug that caused characters that would be escaped internally to be
+ doubled when escaped with a backslash.
+
+u. Fixed the initialization of mailboxes to not cause maildirs to be read
+ (and stat(2) called for every message file) at shell startup.
+
+v. Fixed a bug that caused the shell to not display $PS2 when the read builtin
+ reads a line continued with a backslash.
+
+w. Fixed a bug that caused errors in word splitting when $IFS contained
+ characters used for internal quoting.
+
+x. Fixed bugs that caused problems with output from shell builtins not being
+ completely displayed on some systems.
+
+y. Fixed a bug that caused output to be lost when a redirection is acting on
+ the shell's output file descriptor.
+
+z. Fixed bugs caused by shell builtins not checking for all write errors.
+
+aa. Fixed a problem that caused the shell to dump core if expansions on the
+ pattern passed to the pattern removal word expansions resulted in expansion
+ errors.
+
+bb. Fixed a bug that caused bash to loop infinitely after creating and
+ waiting for 4096 jobs.
+
+cc. Fixed a bug that caused bash to lose the status of a background job under
+ certain circumstances.
+
+dd. Fixed a bug that caused bash to not look in the temporary environment
+ when performing variable lookup under certain circumstances.
+
+ee. Fixed a bug that caused bash to close file descriptors greater than 10
+ when they were used in redirections.
+
+ff. Fixed a problem that caused the shell to attempt to read from the standard
+ input when called as `bash -i script'.
+
+gg. Fixed a memory leak and variable initialization problems when the -v option
+ was supplied to `printf' that could cause incorrect results.
+
+hh. Fixed a bug that caused the `read' builtin to count bytes when the -n option
+ was supplied, rather than (possibly multibyte) characters.
+
+ii. Fixed a bug when displaying a function due to not converting the function
+ to an external form.
+
+jj. Changed job control initialization to ensure that the shell has a tty
+ as its controlling terminal before enabling job control.
+
+kk. Fixed a bug with the `test' builtin that caused it to misinterpret
+ arguments beginning with `-' but containing more than one character.
+
+ll. Fixed bug that could cause the shell to dump core in certain cases where
+ a command sets the SIGINT disposition to the default.
+
+mm. Fixed a bug in the pattern replacement (affecting both word expansion
+ and the `fc' builtin) that occurred when the pattern and replacement
+ strings were empty.
+
+nn. Fixed a bug that caused an arithmetic evaluation error to disable all
+ further evaluation.
+
+oo. Fixed a bug in pathname expansion that caused it to interpret backslashes
+ in the pathname as quoting characters.
+
+pp. Fixed a bug in the replacement getcwd() implementation that could cause
+ memory to be overwritten.
+
+qq. When in Posix mode, the `ulimit' builtin now uses a block size of 512 for
+ the `-c' and `-f' options.
+
+rr. Brace expansion now allows process substitutions to pass through unchanged.
+
+ss. Fixed a problem in the command name completion code to avoid quoting
+ escaped special characters twice when the command name begins with a tilde.
+
+tt. Fixed a problem in the printf builtin that resulted in single-byte
+ output for the "'" escape, even when using multibyte characters.
+
+uu. Fixed a bug that caused the failure exit status to be lost when redirections
+ attached to a compound command failed.
+
+vv. Fixed a bug that caused the internal random number generator to not be
+ re-seeded correctly when creating a subshell.
+
+ww. Fixed a bug that could cause the bash replacement getcwd to overwrite
+ memory.
+
+xx. Fixed a bug that caused the shell to not receive SIGINT if it was sent
+ while the shell was waiting for a command substitution to terminate, and
+ make sure the exit status is correct when it does.
+
+yy. Fixed a bug that resulted in the second and subsequent children spawned
+ by a shell begun to run a command substitution being placed into the
+ wrong process group.
+
+zz. Fixed a bug that caused the results of successful tilde expansion to be
+ subject to pathname expansion and word splitting.
+
+aaa. Fixed a bug that could cause the shell to hang if it encountered an
+ error that caused it to jump back to the top processing loop during a
+ command substitution or `eval' command.
+
+bbb. Fixed a bug that caused the `read' builtin to use the tty's attributes
+ instead of those of the file descriptor passed with the -u option when
+ processing the -n and -d options.
+
+ccc. Fixed a bug that caused incorrect expansion of ${array[@]:foo} if the
+ first character of $IFS was not whitespace.
+
+ddd. Fixed a bug that occurred when scanning for the ending delimiter of a
+ ${parameter/pat/sub} expansion.
+
+eee. Fixed a bug that caused the shell to inappropriately expand command
+ substitutions in words when expanding directory names for completion.
+
+fff. Fixed a bug that caused the `fc' builtin to look too far back in the
+ history list under certain circumstances.
+
+ggg. Fixed a bug that caused a shell running in Posix mode to search $PWD for
+ a file specified as an argument to source/. when the file was not found
+ in $PATH.
+
+hhh. Fixed a bug that caused the shell to modify the case of a command word
+ found via command completion when the shell was performing case-
+ insensitive completion.
+
+iii. Fixed a bug that caused the shell to search $PATH for an argument to
+ source/. even when it contained a `/'.
+
+jjj. Fixed a bug that caused brace expansion to misorder expansions when the
+ locale did not have a collating order like aAbBcC...zZ.
+
+kkk. Fixed a bug that did not allow `set +o history' to have any effect when
+ run in a startup file or from a sourced file.
+
+lll. Fixed a bug with the precedence of the ?: conditional arithmetic operator.
+
+mmm. Fixed a bug that caused side effects of temporary variable assignments
+ to persist in the shell environment.
+
+nnn. Fixed a bug that caused the terminal to be left in non-canonical mode
+ when using editing commands that invoke the an editor on the current
+ command line.
+
+ooo. Fixed a bug that caused globbing characters and characters in $IFS to not
+ be quoted appropriately when displaying assignment statements.
+
+ppp. Fixed a bug that caused the `-e' option to be inherited when sourcing a
+ file or evaluating a command with `eval' even if the return value of the
+ command was supposed to be ignored.
+
+qqq. Fixed a bug that caused the shell to attempt to created variables with
+ invalid names if such names appeared in the initial environment.
+
+rrr. Fixed a bug with quote removal in strings where the final character is a
+ backslash.
+
+sss. Fixed a bug that caused the effects of special variables to persist even
+ when the variables were unset as part of the shell reinitializing itself
+ to execute a shell script.
+
+ttt. Fixed a bug that caused the history to not be saved after `history -c' or
+ `history -d' was executed until a sufficient number of commands had been
+ saved to the history.
+
+uuu. Bash now parses command substitutions according to Posix rules: parsing
+ the command contained in $() to find the closing delimiter.
+
+vvv. Fixed a bug that caused traps on SIGCHLD set in a SIGCHLD handler to
+ not persist.
+
+www. Fixed a bug that didn't allow SIGCHLD to interrupt the `wait' builtin
+ as Posix specifies.
+
+xxx. Invalid numeric arguments to shell builtins no longer cause the shell to
+ short-circuit any executing compound command.
+
+yyy. Fixed a bug that caused the exit status to be lost when `break' was
+ used to short-circuit a loop's execution.
+
+zzz. Fixed a bug that caused stray ^? characters to be left in expansions of
+ "${array[*]}".
+
+aaaa. Bash now prints better error messages for here documents terminated by
+ EOF and for identifying the incorrect token in an invalid arithmetic
+ expression.
+
+bbbb. Fixed a bug in the variable length word expansion that caused it to
+ incorrectly calculate the number of multibyte characters.
+
+cccc. Fixed a race condition that could result in the top-level shell setting
+ the terminal's process group to an incorrect value if the process
+ group was changed by a child of a child of the shell.
+
+dddd. Fixed a bug that caused here documents belonging to commands within a
+ compound command to be displayed in a syntactially-incorrect form, which
+ prevented them from being re-read as input.
+
+eeee. The shell displays more warnings about failures to set the locale.
+
+ffff. Fixed a bug that caused the body of a here-document to not be saved to
+ the history list.
+
+gggg. Fixed a bug that caused configure to incorrectly conclude that FreeBSD
+ had /dev/fd available, resulting in problems with process substitution.
+
+2. Changes to Readline
+
+a. Fixed a number of redisplay errors in environments supporting multibyte
+ characters.
+
+b. Fixed bugs in vi command mode that caused motion commands to inappropriately
+ set the mark.
+
+c. When using the arrow keys in vi insertion mode, readline allows movement
+ beyond the current end of the line (unlike command mode).
+
+d. Fixed bugs that caused readline to loop when the terminal has been taken
+ away and reads return -1/EIO.
+
+e. Fixed bugs in redisplay occurring when displaying prompts containing
+ invisible characters.
+
+f. Fixed a bug that caused the completion append character to not be reset to
+ the default after an application-specified completion function changed it.
+
+g. Fixed a problem that caused incorrect positioning of the cursor while in
+ emacs editing mode when moving forward at the end of a line while using
+ a locale supporting multibyte characters.
+
+h. Fixed an off-by-one error that caused readline to drop every 511th
+ character of buffered input.
+
+i. Fixed a bug that resulted in SIGTERM not being caught or cleaned up.
+
+j. Fixed redisplay bugs caused by multiline prompts with invisible characters
+ or no characters following the final newline.
+
+k. Fixed redisplay bug caused by prompts consisting solely of invisible
+ characters.
+
+l. Fixed a bug in the code that buffers characters received very quickly in
+ succession which caused characters to be dropped.
+
+m. Fixed a bug that caused readline to reference uninitialized data structures
+ if it received a SIGWINCH before completing initialzation.
+
+n. Fixed a bug that caused the vi-mode `last command' to be set incorrectly
+ and therefore unrepeatable.
+
+o. Fixed a bug that caused readline to disable echoing when it was being used
+ with an output file descriptor that was not a terminal.
+
+p. Readline now blocks SIGINT while manipulating internal data structures
+ during redisplay.
+
+q. Fixed a bug in redisplay that caused readline to segfault when pasting a
+ very long line (over 130,000 characters).
+
+r. Fixed bugs in redisplay when using prompts with no visible printing
+ characters.
+
+3. New Features in Bash
+
+a. When using substring expansion on the positional parameters, a starting
+ index of 0 now causes $0 to be prefixed to the list.
+
+b. The `help' builtin now prints its columns with entries sorted vertically
+ rather than horizontally.
+
+c. There is a new variable, $BASHPID, which always returns the process id of
+ the current shell.
+
+d. There is a new `autocd' option that, when enabled, causes bash to attempt
+ to `cd' to a directory name that is supplied as the first word of a
+ simple command.
+
+e. There is a new `checkjobs' option that causes the shell to check for and
+ report any running or stopped jobs at exit.
+
+f. The programmable completion code exports a new COMP_TYPE variable, set to
+ a character describing the type of completion being attempted.
+
+g. The programmable completion code exports a new COMP_KEY variable, set to
+ the character that caused the completion to be invoked (e.g., TAB).
+
+h. If creation of a child process fails due to insufficient resources, bash
+ will try again several times before reporting failure.
+
+i. The programmable completion code now uses the same set of characters as
+ readline when breaking the command line into a list of words.
+
+j. The block multiplier for the ulimit -c and -f options is now 512 when in
+ Posix mode, as Posix specifies.
+
+k. Changed the behavior of the read builtin to save any partial input received
+ in the specified variable when the read builtin times out. This also
+ results in variables specified as arguments to read to be set to the empty
+ string when there is no input available. When the read builtin times out,
+ it returns an exit status greater than 128.
+
+l. The shell now has the notion of a `compatibility level', controlled by
+ new variables settable by `shopt'. Setting this variable currently
+ restores the bash-3.1 behavior when processing quoted strings on the rhs
+ of the `=~' operator to the `[[' command.
+
+m. The `ulimit' builtin now has new -b (socket buffer size) and -T (number
+ of threads) options.
+
+n. The -p option to `declare' now displays all variable values and attributes
+ (or function values and attributes if used with -f).
+
+o. There is a new `compopt' builtin that allows completion functions to modify
+ completion options for existing completions or the completion currently
+ being executed.
+
+p. The `read' builtin has a new -i option which inserts text into the reply
+ buffer when using readline.
+
+q. A new `-E' option to the complete builtin allows control of the default
+ behavior for completion on an empty line.
+
+r. There is now limited support for completing command name words containing
+ globbing characters.
+
+s. Changed format of internal help documentation for all builtins to roughly
+ follow man page format.
+
+t. The `help' builtin now has a new -d option, to display a short description,
+ and a -m option, to print help information in a man page-like format.
+
+u. There is a new `mapfile' builtin to populate an array with lines from a
+ given file.
+
+v. If a command is not found, the shell attempts to execute a shell function
+ named `command_not_found_handle', supplying the command words as the
+ function arguments.
+
+w. There is a new shell option: `globstar'. When enabled, the globbing code
+ treats `**' specially -- it matches all directories (and files within
+ them, when appropriate) recursively.
+
+x. There is a new shell option: `dirspell'. When enabled, the filename
+ completion code performs spelling correction on directory names during
+ completion.
+
+y. The `-t' option to the `read' builtin now supports fractional timeout
+ values.
+
+z. Brace expansion now allows zero-padding of expanded numeric values and
+ will add the proper number of zeroes to make sure all values contain the
+ same number of digits.
+
+aa. There is a new bash-specific bindable readline function: `dabbrev-expand'.
+ It uses menu completion on a set of words taken from the history list.
+
+bb. The command assigned to a key sequence with `bind -x' now sets two new
+ variables in the environment of the executed command: READLINE_LINE_BUFFER
+ and READLINE_POINT. The command can change the current readline line
+ and cursor position by modifying READLINE_LINE_BUFFER and READLINE_POINT,
+ respectively.
+
+cc. There is a new &>> redirection operator, which appends the standard output
+ and standard error to the named file.
+
+dd. The parser now understands `|&' as a synonym for `2>&1 |', which redirects
+ the standard error for a command through a pipe.
+
+ee. The new `;&' case statement action list terminator causes execution to
+ continue with the action associated with the next pattern in the
+ statement rather than terminating the command.
+
+ff. The new `;;&' case statement action list terminator causes the shell to
+ test the next set of patterns after completing execution of the current
+ action, rather than terminating the command.
+
+gg. The shell understands a new variable: PROMPT_DIRTRIM. When set to an
+ integer value greater than zero, prompt expansion of \w and \W will
+ retain only that number of trailing pathname components and replace
+ the intervening characters with `...'.
+
+hh. There are new case-modifying word expansions: uppercase (^[^]) and
+ lowercase (,[,]). They can work on either the first character or
+ array element, or globally. They accept an optional shell pattern
+ that determines which characters to modify. There is an optionally-
+ configured feature to include capitalization operators.
+
+ii. The shell provides associative array variables, with the appropriate
+ support to create, delete, assign values to, and expand them.
+
+jj. The `declare' builtin now has new -l (convert value to lowercase upon
+ assignment) and -u (convert value to uppercase upon assignment) options.
+ There is an optionally-configurable -c option to capitalize a value at
+ assignment.
+
+kk. There is a new `coproc' reserved word that specifies a coprocess: an
+ asynchronous command run with two pipes connected to the creating shell.
+ Coprocs can be named. The input and output file descriptors and the
+ PID of the coprocess are available to the calling shell in variables
+ with coproc-specific names.
+
+4. New Features in Readline
+
+a. A new variable, rl_sort_completion_matches; allows applications to inhibit
+ match list sorting (but beware: some things don't work right if
+ applications do this).
+
+b. A new variable, rl_completion_invoking_key; allows applications to discover
+ the key that invoked rl_complete or rl_menu_complete.
+
+c. The functions rl_block_sigint and rl_release_sigint are now public and
+ available to calling applications who want to protect critical sections
+ (like redisplay).
+
+d. The functions rl_save_state and rl_restore_state are now public and
+ available to calling applications; documented rest of readline's state
+ flag values.
+
+e. A new user-settable variable, `history-size', allows setting the maximum
+ number of entries in the history list.
+
+f. There is a new implementation of menu completion, with several improvements
+ over the old; the most notable improvement is a better `completions
+ browsing' mode.
+
+g. The menu completion code now uses the rl_menu_completion_entry_function
+ variable, allowing applications to provide their own menu completion
+ generators.
+
+h. There is support for replacing a prefix of a pathname with a `...' when
+ displaying possible completions. This is controllable by setting the
+ `completion-prefix-display-length' variable. Matches with a common prefix
+ longer than this value have the common prefix replaced with `...'.
+
+i. There is a new `revert-all-at-newline' variable. If enabled, readline will
+ undo all outstanding changes to all history lines when `accept-line' is
+ executed.
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-3.2-release,
+and the previous version, bash-3.2-beta.
+
+1. Changes to Bash
+
+a. Fixed a bug that caused the temporary environment passed to a command to
+ affect the shell's environment under certain circumstances.
+
+b. Fixed a bug in the printf builtin that caused the %q format specifier to
+ ignore empty string arguments.
+
+c. Improved multibyte character environment detection at configuration time.
+
+d. Fixed a bug in the read builtin that left spurious escape characters in the
+ input after processing backslashes when assigning to an array variable.
+
+2. Changes to Readline
+
+a. Fixed a redisplay bug that occurred in multibyte-capable locales when the
+ prompt was one character longer than the screen width.
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-3.2-beta,
+and the previous version, bash-3.2-alpha.
+
+1. Changes to Bash
+
+a. Changed the lexical analyzer to treat locale-specific blank characters as
+ white space.
+
+b. Fixed a bug in command printing to avoid confusion between redirections and
+ process substitution.
+
+c. Fixed problems with cross-compiling originating from inherited environment
+ variables.
+
+d. Added write error reporting to printf builtin.
+
+e. Fixed a bug in the variable expansion code that could cause a core dump in
+ a multi-byte locale.
+
+f. Fixed a bug that caused substring expansion of a null string to return
+ incorrect results.
+
+g. BASH_COMMAND now retains its previous value while executing commands as the
+ result of a trap, as the documentation states.
+
+2. Changes to Readline
+
+a. Fixed a bug with prompt redisplay in a multi-byte locale to avoid redrawing
+ the prompt and input line multiple times.
+
+b. Fixed history expansion to not be confused by here-string redirection.
+
+c. Readline no longer treats read errors by converting them to newlines, as
+ it does with EOF. This caused partial lines to be returned from readline().
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-3.2-alpha,
+and the previous version, bash-3.1-release.
+
+1. Changes to Bash
+
+a. Fixed a source bug that caused the minimal configuration to not compile.
+
+b. Fixed memory leaks in error handling for the `read' builtin.
+
+c. Changed the [[ and (( compound commands to set PIPESTATUS with their exit
+ status.
+
+d. Fixed some parsing problems with compound array assignments.
+
+e. Added additional configuration changes for: NetBSD (incomplete multibyte
+ character support)
+
+f. Fixed two bugs with local array variable creation when shadowing a variable
+ of the same name from a previous context.
+
+g. Fixed the `read' builtin to restore the correct set of completion functions
+ if a timeout occurs.
+
+h. Added code to defer the initialization of HISTSIZE (and its stifling of the
+ history list) until the history file is loaded, allowing a startup file to
+ override the default value.
+
+i. Tightened up the arithmetic expression parsing to produce better error
+ messages when presented with invalid operators.
+
+j. Fixed the cross-compilation support to build the signal list at shell
+ invocation rather than compile time if cross-compiling.
+
+k. Fixed multibyte support for non-gcc compilers (or compilers that do not
+ allow automatic array variable sizing based on a non-constant value).
+
+l. Several fixes to the code that manages the list of terminated jobs and
+ their exit statuses, and the list of active and recently-terminated jobs
+ to avoid pid aliasing/wraparound and allocation errors.
+
+m. Fixed a problem that allowed scripts to die due to SIGINT while waiting
+ for children, even when started in the background or otherwise ignoring
+ SIGINT.
+
+n. Fixed a bug that caused shells invoked as -/bin/bash from not being
+ recognized as login shells.
+
+o. Fixed a problem that caused shells in the background to give the terminal
+ to a process group other than the foreground shell process group.
+
+p. Fixed a problem with extracting the `varname' in ${#varname}.
+
+q. Fixed the code that handles SIGQUIT to not exit immediately -- thereby
+ calling functions that may not be called in a signal handler context --
+ but set a flag and exit afterward (like SIGINT).
+
+r. Changed the brace expansion code to skip over braces that don't begin a
+ valid matched brace expansion construct.
+
+s. Fixed `typeset' and `declare' to not require that their shell function
+ operands to be valid shell identifiers.
+
+t. Changed `test' to use access(2) with a temporary uid/euid swap when testing
+ file attributes and running setuid, and access(2) in most other cases.
+
+u. Changed completion code to not attempt command name completion on a line
+ consisting solely of whitespace when no_empty_command_completion is set.
+
+v. The `hash' builtin now prints nothing in posix mode when the hash table is
+ empty, and prints a message to that effect to stdout instead of stderr
+ when not in posix mode.
+
+w. Fixed a bug in the extended pattern matching code that caused it to fail to
+ match periods with certain patterns.
+
+x. Fixed a bug that caused the shell to dump core when performing filename
+ generation in directories with thousands of files.
+
+y. Returned to the original Bourne shell rules for parsing ``: no recursive
+ parsing of embedded quoted strings or ${...} constructs.
+
+z. The inheritence of the DEBUG, RETURN, and ERR traps is now dependent only
+ on the settings of the `functrace' and `errtrace' shell options, rather
+ than whether or not the shell is in debugging mode.
+
+aa. Fixed a problem with $HOME being converted to ~ in the expansion of
+ members of the DIRSTACK array.
+
+bb. Fixed a problem with quoted arguments to arithmetic expansions in certain
+ constructs.
+
+cc. The command word completion code now no longer returns matching directories
+ while searching $PATH.
+
+dd. Fixed a bug with zero-padding and precision handling in snprintf()
+ replacement.
+
+ee. Fixed a bug that caused the command substitution code not to take embedded
+ shell comments into account.
+
+ff. Fixed a bug that caused $((...);(...)) to be misinterpreted as an
+ arithmetic substitution.
+
+gg. Fixed a bug in the prompt expansion code that inappropriately added a
+ \001 before a \002 under certain circumstances.
+
+hh. Fixed a bug that caused `unset LANG' to not properly reset the locale
+ (previous versions would set the locale back to what it was when bash
+ was started rather than the system's "native" locale).
+
+ii. Fixed a bug that could cause file descriptors > 10 to not be closed even
+ when closed explicitly by a script.
+
+jj. Fixed a bug that caused single quotes to be stripped from ANSI-C quoting
+ inside double-quoted command substitutions.
+
+kk. Fixed a bug that could cause core dumps when `return' was executed as the
+ last element of a pipeline inside a shell function.
+
+ll. Fixed a bug that caused DEBUG trap strings to overwrite commands stored in
+ the jobs list.
+
+2. Changes to Readline
+
+a. Fixed a problem that caused segmentation faults when using readline in
+ callback mode and typing consecutive DEL characters on an empty line.
+
+b. Fixed several redisplay problems with multibyte characters, all having to
+ do with the different code paths and variable meanings between single-byte
+ and multibyte character redisplay.
+
+c. Fixed a problem with key sequence translation when presented with the
+ sequence \M-\C-x.
+
+d. Fixed a problem that prevented the `a' command in vi mode from being
+ undone and redone properly.
+
+e. Fixed a problem that prevented empty inserts in vi mode from being undone
+ properly.
+
+f. Fixed a problem that caused readline to initialize with an incorrect idea
+ of whether or not the terminal can autowrap.
+
+g. Fixed output of key bindings (like bash `bind -p') to honor the setting of
+ convert-meta and use \e where appropriate.
+
+h. Changed the default filename completion function to call the filename
+ dequoting function if the directory completion hook isn't set. This means
+ that any directory completion hooks need to dequote the directory name,
+ since application-specific hooks need to know how the word was quoted,
+ even if no other changes are made.
+
+i. Fixed a bug with creating the prompt for a non-interactive search string
+ when there are non-printing characters in the primary prompt.
+
+j. Fixed a bug that caused prompts with invisible characters to be redrawn
+ multiple times in a multibyte locale.
+
+k. Fixed a bug that could cause the key sequence scanning code to return the
+ wrong function.
+
+l. Fixed a problem with the callback interface that caused it to fail when
+ using multi-character keyboard macros.
+
+m. Fixed a bug that could cause a core dump when an edited history entry was
+ re-executed under certain conditions.
+
+n. Fixed a bug that caused readline to reference freed memory when attmpting
+ to display a portion of the prompt.
+
+3. New Features in Bash
+
+a. Changed the parameter pattern replacement functions to not anchor the
+ pattern at the beginning of the string if doing global replacement - that
+ combination doesn't make any sense.
+
+b. When running in `word expansion only' mode (--wordexp option), inhibit
+ process substitution.
+
+c. Loadable builtins now work on MacOS X 10.[34].
+
+d. Shells running in posix mode no longer set $HOME, as POSIX requires.
+
+e. The code that checks for binary files being executed as shell scripts now
+ checks only for NUL rather than any non-printing character.
+
+f. Quoting the string argument to the [[ command's =~ operator now forces
+ string matching, as with the other pattern-matching operators.
+
+4. New Features in Readline
+
+a. Calling applications can now set the keyboard timeout to 0, allowing
+ poll-like behavior.
+
+b. The value of SYS_INPUTRC (configurable at compilation time) is now used as
+ the default last-ditch startup file.
+
+c. The history file reading functions now allow windows-like \r\n line
+ terminators.
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-3.1-release,
+and the previous version, bash-3.1-rc2.
+
+1. Changes to Readline
+
+a. Several changes to the multibyte redisplay code to fix problems with
+ prompts containing invisible characters.
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-3.1-rc2,
+and the previous version, bash-3.1-rc1.
+
+1. Changes to Bash
+
+a. Fixed a bug that caused a DEBUG trap to overwrite a command string that's
+ eventually attached to a background job.
+
+b. Changed some code so that filenames with leading tildes with spaces in the
+ name aren't tilde-expanded by the bash completion code.
+
+c. Fixed a bug that caused the pushd builtin to fail to change to
+ directories with leading `-'.
+
+d. Fixed a small memory leak in the programmable completion code.
+
+2. Changes to Readline
+
+a. Fixed a redisplay bug caused by moving the cursor vertically to a line
+ with invisible characters in the prompt in a multibyte locale.
+
+b. Fixed a bug that could cause the terminal special chars to be bound in the
+ wrong keymap in vi mode.
+
+3. New Features in Bash
+
+a. If compiled for strict POSIX conformance, LINES and COLUMNS may now
+ override the true terminal size.
+
+4. New Features in Readline
+
+a. A new external application-controllable variable that allows the LINES
+ and COLUMNS environment variables to set the window size regardless of
+ what the kernel returns.
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-3.1-rc1,
+and the previous version, bash-3.1-beta1.
+
+1. Changes to Bash
+
+a. Fixed a bug that could cause core dumps due to accessing the current
+ pipeline while in the middle of modifying it.
+
+b. Fixed a bug that caused pathnames with backslashes still quoting characters
+ to be passed to opendir().
+
+c. Command word completion now obeys the setting of completion-ignore-case.
+
+d. Fixed a problem with redirection that caused file descriptors greater than
+ 2 to be inappropriately marked as close-on-exec.
+
+e. In Posix mode, after `wait' is called to wait for a particular process
+ explicitly, that process is removed from the list of processes known to
+ the shell, and subsequent attempts to wait for it return errors.
+
+f. Fixed a bug that caused extended pattern matching to incorrectly scan
+ backslash-escaped pattern characters.
+
+g. Fixed a synchronization problem that could cause core dumps when handling
+ a SIGWINCH.
+
+h. Fixed a bug that caused an unmatched backquote to be accepted without an
+ error when processing here documents.
+
+i. Fixed a small memory leak in the `cd' builtin.
+
+j. Fix for MacOS X so it gets the values for the HOSTTYPE, MACHTYPE, and
+ OSTYPE variables at build time, to support universal binaries.
+
+k. Fixed a bug that could cause an exit trap to return the exit status of
+ the trap command rather than the status as it was before the trap was
+ run as the shell's exit status.
+
+2. New Features in Bash
+
+3. Changes to Readline
+
+a. Fixed a bug that caused reversing the incremental search direction to
+ not work correctly.
+
+b. Fixed the vi-mode `U' command to only undo up to the first time insert mode
+ was entered, as Posix specifies.
+
+c. Fixed a bug in the vi-mode `r' command that left the cursor in the wrong
+ place.
+
+4. New Features in Readline
+
+a. New application-callable auxiliary function, rl_variable_value, returns
+ a string corresponding to a readline variable's value.
+
+b. When parsing inputrc files and variable binding commands, the parser
+ strips trailing whitespace from values assigned to boolean variables
+ before checking them.
+
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-3.1-beta1,
+and the previous version, bash-3.1-alpha1.
+
+1. Changes to Bash
+
+a. Added some system-specific signal names.
+
+b. Fixed a typo in the ulimit builtin to make `x' the right option to
+ maniuplate the limit on file locks.
+
+c. Fixed a problem with using += to append to index 0 of an array variable
+ when not using subscript syntax.
+
+d. A few changes to configure.in to remove calls to obsolete or outdated
+ macros.
+
+e. Make sure changes to variables bash handles specially (e.g., LC_ALL) are
+ made when the variable is set in the temporary environment to a command.
+
+f. Make sure changes to variables bash handles specially (e.g., LC_ALL) are
+ made when the variable is modified using `printf -v'.
+
+g. The export environment is now remade on cygwin when HOME is changed, so
+ DLLs bash is linked against pick up the new value. This fixes problems
+ with tilde expansion when linking against and already-installed readline.
+
+h. Small fix to the logic for performing tilde expansion in posix mode, so
+ expansion on the right-hand side of an assignment statement takes place.
+
+i. Fixed a bug that prevented redirections associated with a shell function
+ from being executed when in a subshell.
+
+j. Fixed `source' and `.' builtins to not require an executable file when
+ searching $PATH for a file to source.
+
+k. Fixed a bug that caused incorrect word splitting in a function when IFS
+ was declared local, then unset.
+
+l. Fixed a problem with the `kill' builtin that prevented sending signals
+ to a process group under certain circumstances when providing a pid < 0.
+
+m. When in POSIX mode, `pwd' now checks that the value it prints is the same
+ directory as `.', even when displaying $PWD.
+
+n. Fixed a problem with the `read' builtin when reading a script from standard
+ input and reading data from the same file.
+
+o. Fixed a problem with the `type' and `command' builtins that caused absolute
+ pathnames to be displayed incorrectly.
+
+p. Some changes to the `bg' builtin for POSIX conformance.
+
+q. The `fc' builtin now removes the `fc' command that caused it to invoke an
+ editor on specified history entries from the history entirely, rather than
+ simply ignoring it.
+
+r. When in POSIX mode, the `v' command in vi editing mode simply invokes vi
+ on the current command, rather than checking $FCEDIT and $EDITOR.
+
+s. Fixed a small memory leak in the pathname canonicalization code.
+
+t. Fixed a bug that caused the expanded value of a $'...' string to be
+ incorrectly re-quoted if it occurred within a double-quoted ${...}
+ parameter expansion.
+
+u. Restored default emacs-mode key binding of M-TAB to dynamic-complete-history.
+
+v. Fixed a bug that caused core dumps when interrupting loops running builtins
+ on some systems.
+
+w. Make sure that some of the functions bash provides replacements for are
+ not cpp defines.
+
+x. The code that scans embedded commands for the parser (`...` and $(...)) is
+ now more aware of embedded comments and their effect on quoted strings.
+
+y. Changed the `-n' option to the `history' builtin to not reset the number of
+ history lines read in the current session after reading the new lines from
+ the history file if the history is being appended when it is written to
+ the file, since the appending takes care of the problem that the adjustment
+ was intended to solve.
+
+z. Improved the error message displayed when a shell script fails to execute
+ because the environment and size of command line arguments are too large.
+
+aa. A small fix to make sure that $HISTCMD is evaluated whenever the shell is
+ saving commands to the history list, not just when HISTSIZE is defined.
+
+2. Changes to Readline
+
+a. The `change-case' command now correctly changes the case of multibyte
+ characters.
+
+b. Changes to the shared library construction scripts to deal with Windows
+ DLL naming conventions for Cygwin.
+
+c. Fixed the redisplay code to avoid core dumps resulting from a poorly-timed
+ SIGWINCH.
+
+d. Fixed the non-incremental search code in vi mode to dispose of any current
+ undo list when copying a line from the history into the current editing
+ buffer.
+
+e. The variable assignment code now ignores whitespace at the end of lines
+ when assigning to boolean variables.
+
+f. The `C-w' binding in incremental search now understands multibyte
+ characters.
+
+3. New Features in Bash
+
+a. A new configuration option, `--enable-strict-posix-default', which will
+ build bash to be POSIX conforming by default.
+
+4. New Features in Readline
+
+a. If the rl_completion_query_items is set to a value < 0, readline never
+ asks the user whether or not to view the possible completions.
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-3.1-alpha1,
+and the previous version, bash-3.0-release.
+
+1. Changes to Bash
+
+a. Fixed a bug that caused bash to crash if referencing an unset local array.
+
+b. Fixed a problem that caused tilde expansion to not be performed before
+ attempting globbing word completion.
+
+c. Fixed an incompatibility so that a first argument to trap that's a valid
+ signal number will be trated as a signal rather than a command to execute.
+
+d. Fixed ${#word} expansion to correctly compute the length of a string
+ containing multibyte characters.
+
+e. Fixed a bug that caused bash to not pass the correct flags for signal
+ disposition to child processes.
+
+f. Fixed a bug that caused `fc -l' to list one too many history entries.
+
+g. Some fixes to `fc' for POSIX conformance.
+
+h. Some fixes to job status display for POSIX conformance.
+
+i. Fixed a bug that caused `command -v' to display output if a command was not
+ found -- it should be silent.
+
+j. In POSIX mode, `type' and `command -[vV]' do not report non-executable
+ files, even if the shell will attempt to execute them.
+
+k. Fixed a bug that caused the `==' operator to the [[ command to not attempt
+ extended pattern matching.
+
+l. Fixed the brace expansion code to handle characters whose value exceeds 128.
+
+m. Fixed `printf' to handle strings with a leading `\0' whose length is
+ non-zero.
+
+n. Fixed a couple of problems with brace expansion where `${' was handled
+ incorrectly.
+
+o. Fixed off-by-one error when calculating the upper bound of `offset' when
+ processing the ${array[@]:offset:length} expansion.
+
+p. System-specific configuration changes for: FreeBSD 5.x, Interix, MacOS X
+ 10.4, Linux 2.4+ kernels, Linux 3.x kernels, Dragonfly BSD, QNX 6.x,
+ Cygwin
+
+q. Fixed a bug that caused the shell to ignore the status of the rightmost
+ command in a pipeline when the `pipefail' option was enabled.
+
+r. Fixed a completion bug that caused core dumps when expanding a directory
+ name.
+
+s. Fixed a bug that prevented `hash -d' from removing commands from the hash
+ table.
+
+t. Fixed word splitting to avoid really bad quadratic performance when
+ expanding long lists.
+
+u. Fixed a bug that caused negative offsets in substring expansion to use the
+ wrong values.
+
+v. Fixed a bug in printf that caused it to not return failure on write errors.
+
+w. Fixed a bug that caused commands in subshells to not be properly timed.
+
+x. The shell parser no longer attempts to parse a compound assignment specially
+ unless in a position where an assignment statement is acceptable or parsing
+ arguments to a builtin that accepts assignment statements.
+
+y. Fixed a problem that caused a `case' statement to be added to the history
+ incorrectly as a single command if the `case word' was on one line and the
+ `in' on another.
+
+z. Fixed a problem that caused internal shell quoting characters to be
+ incorrectly quoted with backslashes under some circumstances.
+
+aa. The shell now performs correct word splitting when IFS contains multibyte
+ characters.
+
+bb. The mail checking code now resets the cached file information if the size
+ drops to 0, even if the times don't change.
+
+cc. A completed command name that is found in $PATH as well as the name of a
+ directory in the current directory no longer has a slash appended in certain
+ circumstances: a single instance found in $PATH when `.' is not in $PATH,
+ and multiple instances found in $PATH, even when `.' is in $PATH.
+
+dd. Incorporated tilde expansion into the word expansion code rather than as a
+ separately-called function, fixing some cases where it was performed
+ inappropriately (e.g., after the second `=' in an assignment statement or
+ in a double-quoted parameter expansion).
+
+ee. Fixed several bugs encountered when parsing compound assignment statements,
+ so that compound assignments appearing as arguments to builtins are no
+ longer double-expanded.
+
+ff. Fixed a bug in the command execution code that caused asynchronous commands
+ containing command substitutions to not put the terminal in the wrong
+ process group.
+
+gg. Bash now handles the case where the WCONTINUED flag causes waitpid() to
+ return -1/EINVAL at runtime as well as configuration time.
+
+hh. Fixed parser to generate an error when the pipeline `argument' to `!' or
+ `time' is NULL.
+
+ii. The shell now takes a little more care when manipulating file descriptors
+ greater than 9 with the `exec' builtin.
+
+jj. Fixed a bug that caused variable assignments preceding the `command' builtin
+ preceding a special builtin to be preserved after the command completed in
+ POSIX mode.
+
+kk. Fixed a bug that allowed variables beginning with a digit to be created.
+
+ll. Fixed a bug that caused a \<newline> to be removed when parsing a $'...'
+ construct.
+
+mm. A shell whose name begins with `-' will now be a restricted shell if the
+ remainder of the name indicates it should be restricted.
+
+nn. Fixed a bug that could cause a core dump if FUNCNAME were changed or unset
+ during a function's execution.
+
+oo. Fixed a bug that caused executing a `return' in a function to not execute
+ a RETURN trap. The RETURN trap is inherited by shell functions only if
+ function tracing is globally enabled or has been enabled for that function.
+
+pp. Fixed cases where var[@] was not handled exactly like var, when var is a
+ scalar variable.
+
+qq. Fixed a bug that caused the first character after a SIGINT to be discarded
+ under certain circumstances.
+
+rr. Fixed exit status code so that a suspended job returns 128+signal as its
+ exit status (preventing commands after it in `&&' lists from being
+ executed).
+
+ss. Fixed a bug that caused the shell parser state to be changed by executing
+ a shell function as a result of word completion.
+
+tt. Fixed a long-standing bug that caused '\177' characters in variable
+ values to be discarded when expanded in double-quoted strings.
+
+uu. Fixed a bug that caused $RANDOM to be re-seeded multiple times in a
+ subshell environment.
+
+vv. Extensive changes to the job management code to avoid the pid-reuse and
+ pid-aliasing problems caused by retaining the exit status of too many jobs,
+ but still retain as many background job statuses as POSIX requires.
+
+ww. Fixed a parser bug in processing \<newline> that caused things like
+
+ ((echo 5) \
+ (echo 6))
+
+ to not work correctly.
+
+xx. `pwd -P' now sets $PWD to a directory name containing no symbolic links
+ when in posix mode, as POSIX requires.
+
+yy. In posix mode, bash no longer sets $PWD to a name containing no symbolic
+ links if a directory is chosen from $CDPATH.
+
+zz. The word splitting code now treats an IFS character that is not space,
+ tab, or newline and any adjacent IFS white space as a single delimiter, as
+ SUSv3/XPG6 require.
+
+aaa. The `read' builtin now checks whether or not the number of fields read is
+ exactly the same as the number of variables instead of just assigning the
+ rest of the line (minus any trailing IFS white space) to the last
+ variable. This is what POSIX/SUS/XPG all require.
+
+bbb. Fixed a bug that caused `read' to always check whether or not fd 0 was a
+ pipe, even when reading from another file descriptor.
+
+ccc. Fixed a bug that caused short-circuiting of execution even if the return
+ value was being inverted.
+
+ddd. Fixed a bug that caused a core dump while decoding \W escapes in PS1 if
+ PWD was unset.
+
+eee. Fixed a bug in `read' that counted internal quoting characters for the
+ purposes of `read -n'.
+
+fff. Fixed a bug so that a function definition in a pipeline causes a child
+ process to be forked at the right time.
+
+ggg. Bash will not attempt to link against a readline library that doesn't
+ have rl_gnu_readline_p == 1.
+
+hhh. Fixed a bug that caused `read' to consume one too many characters when
+ reading a fixed number of characters and the Nth character is a backslash.
+
+iii. Fixed a bug that caused `unset' on variables in the temporary environment
+ to leave them set when `unset' completed.
+
+jjj. Fixed a bug that caused bash to close fd 2 if an `exec' failed and the
+ shell didn't exit.
+
+kkk. The completion code is more careful to not turn `/' or `///' into `//',
+ for those systems on which `//' has special meaning.
+
+lll. Fixed a bug that caused command substitution in asynchronous commands to
+ close the wrong file descriptors.
+
+mmm. The shell no longer prints status messages about terminated background
+ processes unless job control is active.
+
+nnn. Fixed a bug that prevented multiple consecutive invocations of `history -s'
+ from adding all the commands to the history list.
+
+ooo. Added a couple of changes to make arithmetic expansion more consistent in
+ all its contexts (still not perfect).
+
+ppp. Fixed a bug that caused the parser to occasionally not find the right
+ terminating "`" in an old-style command substitution.
+
+qqq. Fixed a bug that caused core dumps when the shell was reading its non-
+ interactive input from fd 0 and fd 0 was duplicated and restored using a
+ combination of `exec' (to save) and redirection (to restore).
+
+rrr. Fixed a problem that caused loops in sourced scripts to not be cleaned
+ up properly when a `return' is executed.
+
+sss. Change internal command substitution completion function to append a slash
+ to directory names in the command.
+
+2. Changes to Readline
+
+a. Fixed a bug that caused multiliine prompts to be wrapped and displayed
+ incorrectly.
+
+b. Fixed a bug that caused ^P/^N in emacs mode to fail to display the current
+ line correctly.
+
+c. Fixed a problem in computing the number of invisible characters on the first
+ line of a prompt whose length exceeds the screen width.
+
+d. Fixed vi-mode searching so that failure preserves the current line rather
+ than the last line in the history list.
+
+e. Fixed the vi-mode `~' command (change-case) to have the correct behavior at
+ end-of-line when manipulating multibyte characters.
+
+f. Fixed the vi-mode `r' command (change-char) to have the correct behavior at
+ end-of-line when manipulating multibyte characters.
+
+g. Fixed multiple bugs in the redisplay of multibyte characters: displaying
+ prompts longer than the screen width containing multibyte characters,
+
+h. Fix the calculation of the number of physical characters in the prompt
+ string when it contains multibyte characters.
+
+i. A non-zero value for the `rl_complete_suppress_append' variable now causes
+ no `/' to be appended to a directory name.
+
+j. Fixed forward-word and backward-word to work when words contained
+ multibyte characters.
+
+k. Fixed a bug in finding the delimiter of a `?' substring when performing
+ history expansion in a locale that supports multibyte characters.
+
+l. Fixed a memory leak caused by not freeing the timestamp in a history entry.
+
+m. Fixed a bug that caused "\M-x" style key bindings to not obey the setting
+ of the `convert-meta' variable.
+
+n. Fixed saving and restoring primary prompt when prompting for incremental
+ and non-incremental searches; search prompts now display multibyte
+ characters correctly.
+
+o. Fixed a bug that caused keys originally bound to self-insert but shadowed
+ by a multi-character key sequence to not be inserted.
+
+p. Fixed code so rl_prep_term_function and rl_deprep_term_function aren't
+ dereferenced if NULL (matching the documentation).
+
+q. Extensive changes to readline to add enough state so that commands
+ requiring additional characters (searches, multi-key sequences, numeric
+ arguments, commands requiring an additional specifier character like
+ vi-mode change-char, etc.) work without synchronously waiting for
+ additional input.
+
+r. Lots of changes so readline builds and runs on MinGW.
+
+s. Readline no longer tries to modify the terminal settings when running in
+ callback mode.
+
+t. The Readline display code no longer sets the location of the last invisible
+ character in the prompt if the \[\] sequence is empty.
+
+3. New Features in Bash
+
+a. Bash now understands LC_TIME as a special variable so that time display
+ tracks the current locale.
+
+b. BASH_ARGC, BASH_ARGV, BASH_SOURCE, and BASH_LINENO are no longer created
+ as `invisible' variables and may not be unset.
+
+c. In POSIX mode, if `xpg_echo' option is enabled, the `echo' builtin doesn't
+ try to interpret any options at all, as POSIX requires.
+
+d. The `bg' builtin now accepts multiple arguments, as POSIX seems to specify.
+
+e. Fixed vi-mode word completion and glob expansion to perform tilde
+ expansion.
+
+f. The `**' mathematic exponentiation operator is now right-associative.
+
+g. The `ulimit' builtin has new options: -i (max number of pending signals),
+ -q (max size of POSIX message queues), and -x (max number of file locks).
+
+h. A bare `%' once again expands to the current job when used as a job
+ specifier.
+
+i. The `+=' assignment operator (append to the value of a string or array) is
+ now supported for assignment statements and arguments to builtin commands
+ that accept assignment statements.
+
+j. BASH_COMMAND now preserves its value when a DEBUG trap is executed.
+
+k. The `gnu_errfmt' option is enabled automatically if the shell is running
+ in an emacs terminal window.
+
+l. New configuration option: --single-help-strings. Causes long help text
+ to be written as a single string; intended to ease translation.
+
+m. The COMP_WORDBREAKS variable now causes the list of word break characters
+ to be emptied when the variable is unset.
+
+n. An unquoted expansion of $* when $IFS is empty now causes the positional
+ parameters to be concatenated if the expansion doesn't undergo word
+ splitting.
+
+o. Bash now inherits $_ from the environment if it appears there at startup.
+
+p. New shell option: nocasematch. If non-zero, shell pattern matching ignores
+ case when used by `case' and `[[' commands.
+
+q. The `printf' builtin takes a new option: -v var. That causes the output
+ to be placed into var instead of on stdout.
+
+r. By default, the shell no longer reports processes dying from SIGPIPE.
+
+s. Bash now sets the extern variable `environ' to the export environment it
+ creates, so C library functions that call getenv() (and can't use the
+ shell-provided replacement) get current values of environment variables.
+
+4. New Features in Readline
+
+a. The key sequence sent by the keypad `delete' key is now automatically
+ bound to delete-char.
+
+b. A negative argument to menu-complete now cycles backward through the
+ completion list.
+
+c. A new bindable readline variable: bind-tty-special-chars. If non-zero,
+ readline will bind the terminal special characters to their readline
+ equivalents when it's called (on by default).
+
+d. New bindable command: vi-rubout. Saves deleted text for possible
+ reinsertion, as with any vi-mode `text modification' command; `X' is bound
+ to this in vi command mode.
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-3.0-release,
+and the previous version, bash-3.0-rc1.
+
+1. Changes to Bash
+
+a. Fixed a boundary overrun that could cause segmentation faults when the
+ completion code hands an incomplete construct to the word expansion
+ functions.
+
+b. Changed posix mode behavior so that an error in a variable assignment
+ preceding a special builtin causes a non-interactive shell to exit.
+
+c. Change the directory expansion portion of the completion code to not
+ expand embedded command substitutions if the directory name appears in
+ the file system.
+
+d. Fixed a problem that caused `bash -r' to turn on restrictions before
+ reading the startup files.
+
+e. Fixed a problem with the default operation of the `umask' builtin.
+
+2. Changes to Readline
+
+a. Fixed a problem with readline saving the contents of the current line
+ before beginning a non-interactive search.
+
+b. Fixed a problem with EOF detection when using rl_event_hook.
+
+c. Fixed a problem with the vi mode `p' and `P' commands ignoring numeric
+ arguments.
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-3.0-rc1,
+and the previous version, bash-3.0-beta1.
+
+1. Changes to Bash
+
+a. Fixed a bug that caused incorrect behavior when referecing element 0 of
+ an array using $array, element 0 was unset, and `set -u' was enabled.
+
+b. System-specific changes for: SCO Unix 3.2, Tandem.
+
+c. Fixed a bug that caused inappropriate word splitting when a variable was
+ expanded within a double-quoted string that also included $@.
+
+d. Fixed a bug that caused `pwd' to not display anything in physical mode
+ when the file system had changed underneath the shell.
+
+e. Fixed a bug in the pre- and post- increment and decrement parsing in the
+ expression evaluator that caused errors when the operands and corresponding
+ operators were separated by whitespace.
+
+f. Fixed a bug that caused `history -p' to add an entry to the history list,
+ counter to the documentation. (Keeps the history expansions invoked by
+ emacs-mode command line editing from doing that as well.)
+
+g. Fixed a bug that could cause a core dump if `cd' is asked to print out a
+ pathname longer than PATH_MAX characters.
+
+h. Fixed a bug that caused jobs to be put into the wrong process group under
+ some circumstances after enabling job control with `set -m'.
+
+i. `unalias' now returns failure if no alias name arguments are supplied.
+
+j. Documented the characters not allowed to appear in an alias name.
+
+k. $* is no longer expanded as if in double quotes when it appears in the
+ body of a here document, as the SUS seems to require.
+
+l. The `bashbug' script now uses a directory in $TMPDIR for exclusive
+ access rather than trying to guess how the underlying OS provides for
+ secure temporary file creation.
+
+m. Fixed a few problems with `cd' and `pwd' when asked to operate on pathnames
+ longer than PATH_MAX characters.
+
+n. Fixed a memory leak caused when creating multiple local array variables
+ with identical names.
+
+o. Fixed a problem with calls to getcwd() so that bash now operates better
+ when the full pathname to the current directory is longer than PATH_MAX
+ bytes.
+
+p. The `trap' builtin now reports an error if a single non-signal argument
+ is specified.
+
+q. Fixed a bug that caused `umask' to not work correctly when presented
+ with a mask of all 0s.
+
+r. When `getopts' reaches the end of options, OPTARG is unset, as POSIX
+ appears to specify.
+
+s. Interactive mode now depends on whether or not stdin and stderr are
+ connected to a tty; formerly it was stdin and stdout. POSIX requires
+ this.
+
+t. Fixed vi-mode completion to work more as POSIX specifies (e.g., doing the
+ right kind of filename generation).
+
+2. Changes to Readline
+
+a. Fixed a problem that could cause readline to refer to freed memory when
+ moving between history lines while doing searches.
+
+b. Improvements to the code that expands and displays prompt strings
+ containing multibyte characters.
+
+c. Fixed a problem with vi-mode not correctly remembering the numeric argument
+ to the last `c'hange command for later use with `.'.
+
+d. Fixed a bug in vi-mode that caused multi-digit count arguments to work
+ incorrectly.
+
+e. Fixed a problem in vi-mode that caused the last text modification command
+ to not be remembered across different command lines.
+
+f. Fixed problems with changing characters and changing case at the end of
+ the line.
+
+3. New Features in Bash
+
+a. The `jobs', `kill', and `wait' builtins now accept job control notation
+ even if job control is not enabled.
+
+b. The historical behavior of `trap' that allows a missing `action' argument
+ to cause each specified signal's handling to be reset to its default is
+ now only supported when `trap' is given a single non-option argument.
+
+4. New Features in Readline
+
+a. When listing completions, directories have a `/' appended if the
+ `mark-directories' option has been enabled.
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-3.0-beta1,
+and the previous version, bash-3.0-alpha.
+
+1. Changes to Bash
+
+a. Fixes to build correctly when arrays are not compiled into the shell.
+
+b. Fixed command substitution to run any exit trap defined in the command
+ substitution before returning; the exit trap is not inherited from the
+ calling shell.
+
+c. Fixes to process group synchronization code so that every child process
+ attempts to set the terminal's process group; fixes some synchronization
+ problems on Linux kernels that schedule the child to always run before
+ the parent.
+
+d. Fixed processing of octal and hex constants in printf builtin for POSIX.2
+ compliance.
+
+e. Fixed a couple of core dumps in the pattern removal code.
+
+f. Fixes to the array subrange extraction code to deal better with sparse
+ arrays.
+
+g. Parser errors and other errors that result in the shell exiting now cause
+ the exit trap to be run.
+
+h. Change the command substitution completion functions to not append any
+ closing quote, because it would be inserted a closing "`" or ")".
+
+i. Fix history initialization so assignments to $histchars made in startup
+ files are honored.
+
+j. If an exit trap does not contain a call to `exit', the shell now uses
+ the exit status of the last command executed before the trap as the exit
+ status of the shell.
+
+k. The parser now prompts with $PS2 if it reads a newline while parsing a
+ compound array assignment statement.
+
+l. When performing a compound array assignment, the parser doesn't treat
+ words of the form [index]=value as assignments if they're the result of
+ expansions.
+
+m. Fixed a bug that caused `return' executed in a trap command to make the
+ shell think it was still running the trap.
+
+n. Fixed the value of errno set by the pathname canonicalization functions.
+
+o. Changed the grammar so that `time' alone on a line times a null command
+ rather than being a syntax error.
+
+p. The pattern substitution code no longer performs quote removal on the
+ pattern before trying to match it, as the pattern removal functions do.
+
+q. Fixed a bug that could cause core dumps when checking whether a quoted
+ command name was being completed.
+
+r. Fixes to the pattern removal and pattern replacement expansions to deal
+ with multibyte characters better (and faster).
+
+s. Fix to the substring expansion (${param:off[:len]}) to deal with (possibly
+ multibyte) characters instead of raw bytes.
+
+t. Fixed a bug that caused some key bindings set in an inputrc to be ignored
+ at shell startup.
+
+u. Fixed a bug that caused unsetting a local variable within a function to
+ not work correctly.
+
+v. Fixed a bug that caused invalid variables to be created when using
+ `read -a'.
+
+w. Fixed a bug that caused "$@" to expand incorrectly when used as the right
+ hand side of a parameter expansion such as ${word:="$@"} if the first
+ character of $IFS was not a space.
+
+x. Fixed a slight cosmetic problem when printing commands containing a
+ `>&word' redirection.
+
+y. Fixed a problem that could cause here documents to not be created correctly
+ if the system temporary directory did not allow writing.
+
+2. Changes to Readline
+
+a. Change to history expansion functions to treat `^' as equivalent to word
+ one, as the documention states.
+
+b. Some changes to the display code to improve display and redisplay of
+ multibyte characters.
+
+c. Changes to speed up the multibyte character redisplay code.
+
+d. Fixed a bug in the vi-mode `E' command that caused it to skip over the
+ last character of a word if invoked while point was on the word's
+ next-to-last character.
+
+e. Fixed a bug that could cause incorrect filename quoting when
+ case-insensitive completion was enabled and the word being completed
+ contained backslashes quoting word break characters.
+
+f. Fixed a bug in redisplay triggered when the prompt string contains
+ invisible characters.
+
+g. Fixed some display (and other) bugs encountered in multibyte locales
+ when a non-ascii character was the last character on a line.
+
+h. Fixed some display bugs caused by multibyte characters in prompt strings.
+
+i. Fixed a problem with history expansion caused by non-whitespace characters
+ used as history word delimiters.
+
+3. New Features in Bash
+
+a. printf builtin understands two new escape sequences: \" and \?.
+
+b. `echo -e' understands two new escape sequences: \" and \?.
+
+c. The GNU `gettext' package and libintl have been integrated; the shell's
+ messages can be translated into different languages.
+
+d. The `\W' prompt expansion now abbreviates $HOME as `~', like `\w'.
+
+e. The error message printed when bash cannot open a shell script supplied
+ as argument 1 now includes the name of the shell, to better identify
+ the error as coming from bash.
+
+4. New Features in Readline
+
+a. New application variable, rl_completion_quote_character, set to any
+ quote character readline finds before it calls the application completion
+ function.
+
+b. New application variable, rl_completion_suppress_quote, settable by an
+ application completion function. If set to non-zero, readline does not
+ attempt to append a closing quote to a completed word.
+
+c. New application variable, rl_completion_found_quote, set to a non-zero
+ value if readline determines that the word to be completed is quoted.
+ Set before readline calls any application completion function.
+
+d. New function hook, rl_completion_word_break_hook, called when readline
+ needs to break a line into words when completion is attempted. Allows
+ the word break characters to vary based on position in the line.
+
+e. New bindable command: unix-filename-rubout. Does the same thing as
+ unix-word-rubout, but adds `/' to the set of word delimiters.
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-3.0-alpha,
+and the previous version, bash-2.05b-release.
+
+1. Changes to Bash
+
+a. Fixes so that the shell will compile without some of the default options
+ defined.
+
+b. Fixed an error message that did not pass enough arguments to printf.
+
+c. Fixed a bug that caused input redirection to a builtin inside a script
+ being read from standard input to result in the rest of the already-
+ read and buffered script to be discarded.
+
+d. Fixed a bug that caused subshell initialization to close the file
+ descriptor from which the shell was reading a script under certain
+ circumstances.
+
+e. Fixed a bug that caused the shell to not advance a string pointer over
+ a null wide character when doing string operations.
+
+f. Fixed the internal logout code so that shells that time out waiting for
+ input (using $TMOUT) run ~/.bash_logout.
+
+g. Portability and configuration changes for: cygwin, HP/UX, GNU/FreeBSD.
+
+h. The parser no longer adds implicit double quotes to ((...)) arithmetic
+ commands.
+
+i. The ((...)) arithmetic command evaluation code was fixed to not dump core
+ when the expanded string is null.
+
+j. The ((...)) arithmetic command evaluation code was fixed to not perform
+ variable assignments while expanding the expression.
+
+k. Fixed a bug that caused word splitting to be performed incorrectly when
+ IFS is set, but null.
+
+l. Fixed a bug in brace expansion that caused a quoted `$' preceding an
+ open brace to inhibit brace expansion.
+
+m. Fixed a bug that caused a leading `-' in the shell's name to cause it to
+ not be recognized as a restricted shell.
+
+n. Fixed a bug in the arithmetic evaluation code that could cause longjmps
+ to an invalid location and result in a core dump.
+
+o. Fixed a bug in the calculation of how many history lines are new in a
+ single shell session when reading new history lines from a file with
+ `history -n'.
+
+p. Fixed a bug in pathname canonicalization that caused the shell to dump
+ core when presented with a pathname longer than PATH_MAX.
+
+q. Fixed the parser so that it doesn't try to compare a char variable to
+ EOF, which fails when chars are unsigned.
+
+r. Fixed a bug in the simple command execution code that caused occasional
+ core dumps.
+
+s. The shell does a better job of saving any partial parsing state during
+ operations which cause a command to be executed while a line is being
+ entered and parsed.
+
+t. The completion code now splits words more like the expansion code when
+ $IFS is used to split.
+
+u. The locale code does a better job of recomputing the various locale
+ variable values when LC_ALL is unset.
+
+v. The programmable completion code does a better job of dequoting expanded
+ word lists before comparing them against the word to be matched.
+
+w. The shell no longer seg faults if the expanded value of $PS4 is null
+ and `set -x' is enabled.
+
+x. Fixed a bug that caused core dumps when a here string expanded to NULL.
+
+y. The mail checking code now makes sure the mailbox is bigger before
+ reporting the existence of new mail.
+
+z. The parser does not try to expand $'...' and $"..." when the appear
+ within double quotes unless the `extquote' option has been enabled with
+ `shopt'. For backwards compatibility, it is enabled by default.
+
+aa. Fixed a bug that caused `for x; do ...' and `select x; do ... to use
+ $@ instead of "$@" for the implicit list of arguments.
+
+bb. Fixed a bug that caused a subshell of a restricted shell (e.g., one
+ spawned to execute a pipeline) to not exit immediately if attempting
+ to use a command containing a slash.
+
+cc. Fixed a problem with empty replacements for a pattern that doesn't match
+ when performing ${param/word/} expansion.
+
+dd. Word expansions performed while expanding redirections no longer search
+ a command's temporary environment to expand variable values.
+
+ee. Improvements to the alias expansion code when expanding subsequent words
+ because an aliase's value ends with a space.
+
+ff. `cd -' now prints the current working directory after a successful chdir
+ even when the shell is not interactive, as the standard requires.
+
+gg. The shell does a better job of ensuring a child process dies of SIGINT
+ before resending SIGINT to itself.
+
+hh. The arithmetic expansion variable assignment code now does the right
+ thing when assigning to `special' variables like OPTIND.
+
+ii. When history expansion verification is enabled, the bash readline helper
+ functions that do history expansion on the current line don't print
+ the results.
+
+jj. Fixed bugs with multiple consecutive alias expansion when one of the
+ expansions ends with a space.
+
+kk. Fixed a problem in the programmable completion code that could cause core
+ dumps when trying to initialize a set of possible completions from a
+ list of variables.
+
+ll. The \[ and \] escape characters are now ignored when decoding the prompt
+ string if the shell is started with editing disabled.
+
+mm. Fixed a bug that could leave extra characters in a string when doing
+ quoted null character removal.
+
+nn. Command substitution and other subshell operations no longer reset the
+ line number (aids the bash debugger).
+
+oo. Better line number management when executing simple commands, conditional
+ commands, for commands, and select commands.
+
+pp. The globbing code now uses malloc, with its better failure properties,
+ rather than alloca().
+
+qq. Fixed a bug that caused expansions like #{a[2]:=value} to create the
+ appropriate array element instead of a variable named `a[2]'.
+
+rr. Fixed a bug in the handling of a `?(...)' pattern immediately following
+ a `*' when extglob is enabled.
+
+ss. Fixed a bug that caused a `return' invoked in an exit trap when exit is
+ invoked in a function to misbehave.
+
+tt. Fixed a bug that caused CTLESC and CTLNUL characters to not be escaped
+ by the internal shell string quoting functions.
+
+uu. Fixed a bug that caused quoted null characters in an expanded word list
+ to be inappropriately assigned to an array variable when using `read -a'.
+
+vv. Fixed a bug that caused redirections accompanying a null command to persist
+ in the current shell.
+
+ww. Fixed a bug that caused the prompt to be printed when the shell was
+ expanding a multiline alias.
+
+xx. Fixed a bug that resulted in core dumps when the completion for a command
+ changed the compspec.
+
+yy. Fixed a bug that caused evaluation of programmable completions to print
+ notifications of completed jobs.
+
+zz. Bash now disables line editing when $EMACS == `t' and $TERM == `dumb'
+ (which is what emacs shell windows do).
+
+aaa. In posix mode, `kill -l' causes signal names to be displayed without
+ a leading `SIG'.
+
+bbb. Clear error flag on standard output so it doesn't persist across multiple
+ builtin commands.
+
+ccc. In posix mode, `alias' displays alias values without the leading `alias',
+ so the output cannot be used as subsequent input.
+
+ddd. In posix mode, the `trap' builtin doesn't check whether or not its
+ first argument is a signal specification and revert the signal handling
+ to its original disposition if it is.
+
+eee. Fixed several bugs in the handling of "$*" and "${array[*]}" by the
+ pattern substitution and removal expansions.
+
+fff. Fixed several problems with the handling of ${array[@]}, ${array[*]},
+ $@, and $* by the indirect variable expansion code.
+
+ggg. Fixed a bug that did not allow `time' to be aliased.
+
+hhh. Improved the mail checking code so it won't check (and possibly cause an
+ NFS file system mount) until MAILPATH or MAIL is given a value -- there
+ is no default if DEFAULT_MAIL_DIRECTORY is not defined at compile time.
+ (It is computed by configure, but can be #undef'd in config-bot.h.)
+
+iii. If the `chkwinsize' option is enabled, the shell checks for window size
+ changes if a child process exits due to a signal.
+
+jjj. Removed the attempts to avoid adding a slash at the end of a completed
+ executable name if there was a directory with the same name in the
+ current directory.
+
+kkk. Fixed PATH lookup code so it treats the permission bits separately for
+ owner, group, and other, rather than checking them all.
+
+lll. Fixed the locale code to reset the parser's idea of the character class
+ <blank>, which controls how it splits tokens, when the locale changes.
+
+mmm. The shell now binds its special readline functions and key bindings only
+ if the user's inputrc file has not already bound them.
+
+nnn. The shell now reports on processes that dump core due to signals when
+ invoked as `-c command'.
+
+2. Changes to Readline
+
+a. Fixes to avoid core dumps because of null pointer references in the
+ multibyte character code.
+
+b. Fix to avoid infinite recursion caused by certain key combinations.
+
+c. Fixed a bug that caused the vi-mode `last command' to be set incorrectly.
+
+d. Readline no longer tries to read ahead more than one line of input, even
+ when more is available.
+
+e. Fixed the code that adjusts the point to not mishandle null wide
+ characters.
+
+f. Fixed a bug in the history expansion `g' modifier that caused it to skip
+ every other match.
+
+g. Fixed a bug that caused the prompt to overwrite previous output when the
+ output doesn't contain a newline and the locale supports multibyte
+ characters. This same change fixes the problem of readline redisplay
+ slowing down dramatically as the line gets longer in multibyte locales.
+
+h. History traversal with arrow keys in vi insertion mode causes the cursor
+ to be placed at the end of the new line, like in emacs mode.
+
+i. The locale initialization code does a better job of using the right
+ precedence and defaulting when checking the appropriate environment
+ variables.
+
+j. Fixed the history word tokenizer to handle <( and >( better when used as
+ part of bash.
+
+k. The overwrite mode code received several bug fixes to improve undo.
+
+l. Many speedups to the multibyte character redisplay code.
+
+m. The callback character reading interface should not hang waiting to read
+ keyboard input.
+
+n. Fixed a bug with redoing vi-mode `s' command.
+
+o. The code that initializes the terminal tracks changes made to the terminal
+ special characters with stty(1) (or equivalent), so that these changes
+ are reflected in the readline bindings. New application-callable function
+ to make it work: rl_tty_unset_default_bindings().
+
+p. Fixed a bug that could cause garbage to be inserted in the buffer when
+ changing character case in vi mode when using a multibyte locale.
+
+q. Fixed a bug in the redisplay code that caused problems on systems
+ supporting multibyte characters when moving between history lines when the
+ new line has more glyphs but fewer bytes.
+
+r. Undo and redo now work better after exiting vi insertion mode.
+
+s. Make sure system calls are restarted after a SIGWINCH is received using
+ SA_RESTART.
+
+t. Improvements to the code that displays possible completions when using
+ multibyte characters.
+
+u. Fixed a problem when parsing nested if statements in inputrc files.
+
+v. The completer now takes multibyte characters into account when looking for
+ quoted substrings on which to perform completion.
+
+w. The history search functions now perform better bounds checking on the
+ history list.
+
+3. New Features in Bash
+
+a. ANSI string expansion now implements the \x{hexdigits} escape.
+
+b. There is a new loadable `strftime' builtin.
+
+c. New variable, COMP_WORDBREAKS, which controls the readline completer's
+ idea of word break characters.
+
+d. The `type' builtin no longer reports on aliases unless alias expansion
+ will actually be performed.
+
+e. HISTCONTROL is now a colon-separated list of values, which permits
+ more extensibility and backwards compatibility.
+
+f. HISTCONTROL may now include the `erasedups' option, which causes all lines
+ matching a line being added to be removed from the history list.
+
+g. `configure' has a new `--enable-multibyte' argument that permits multibyte
+ character support to be disabled even on systems that support it.
+
+h. New variables to support the bash debugger: BASH_ARGC, BASH_ARGV,
+ BASH_SOURCE, BASH_LINENO, BASH_SUBSHELL, BASH_EXECUTION_STRING,
+ BASH_COMMAND
+
+i. FUNCNAME has been changed to support the debugger: it's now an array
+ variable.
+
+j. for, case, select, arithmetic commands now keep line number information
+ for the debugger.
+
+k. There is a new `RETURN' trap executed when a function or sourced script
+ returns (not inherited child processes; inherited by command substitution
+ if function tracing is enabled and the debugger is active).
+
+l. New invocation option: --debugger. Enables debugging and turns on new
+ `extdebug' shell option.
+
+m. New `functrace' and `errtrace' options to `set -o' cause DEBUG and ERR
+ traps, respectively, to be inherited by shell functions. Equivalent to
+ `set -T' and `set -E' respectively. The `functrace' option also controls
+ whether or not the DEBUG trap is inherited by sourced scripts.
+
+n. The DEBUG trap is run before binding the variable and running the action
+ list in a `for' command, binding the selection variable and running the
+ query in a `select' command, and before attempting a match in a `case'
+ command.
+
+o. New `--enable-debugger' option to `configure' to compile in the debugger
+ support code.
+
+p. `declare -F' now prints out extra line number and source file information
+ if the `extdebug' option is set.
+
+q. If `extdebug' is enabled, a non-zero return value from a DEBUG trap causes
+ the next command to be skipped, and a return value of 2 while in a
+ function or sourced script forces a `return'.
+
+r. New `caller' builtin to provide a call stack for the bash debugger.
+
+s. The DEBUG trap is run just before the first command in a function body is
+ executed, for the debugger.
+
+t. `for', `select', and `case' command heads are printed when `set -x' is
+ enabled.
+
+u. There is a new {x..y} brace expansion, which is shorthand for {x.x+1,
+ x+2,...,y}. x and y can be integers or single characters; the sequence
+ may ascend or descend; the increment is always 1.
+
+v. New ksh93-like ${!array[@]} expansion, expands to all the keys (indices)
+ of array.
+
+w. New `force_fignore' shopt option; if enabled, suffixes specified by
+ FIGNORE cause words to be ignored when performing word completion even
+ if they're the only possibilities.
+
+x. New `gnu_errfmt' shopt option; if enabled, error messages follow the `gnu
+ style' (filename:lineno:message) format.
+
+y. New `-o bashdefault' option to complete and compgen; if set, causes the
+ whole set of bash completions to be performed if the compspec doesn't
+ result in a match.
+
+z. New `-o plusdirs' option to complete and compgen; if set, causes directory
+ name completion to be performed and the results added to the rest of the
+ possible completions.
+
+aa. `kill' is available as a builtin even when the shell is built without
+ job control.
+
+bb. New HISTTIMEFORMAT variable; value is a format string to pass to
+ strftime(3). If set and not null, the `history' builtin prints out
+ timestamp information according to the specified format when displaying
+ history entries. If set, bash tells the history library to write out
+ timestamp information when the history file is written.
+
+cc. The [[ ... ]] command has a new binary `=~' operator that performs
+ extended regular expression (egrep-like) matching.
+
+dd. `configure' has a new `--enable-cond-regexp' option (enabled by default)
+ to enable the =~ operator and regexp matching in [[ ... ]].
+
+ee. Subexpressions matched by the =~ operator are placed in the new
+ BASH_REMATCH array variable.
+
+ff. New `failglob' option that causes an expansion error when pathname
+ expansion fails to produce a match.
+
+gg. New `set -o pipefail' option that causes a pipeline to return a failure
+ status if any of the processes in the pipeline fail, not just the last
+ one.
+
+4. New Features in Readline
+
+a. History expansion has a new `a' modifier equivalent to the `g' modifier
+ for compatibility with the BSD csh.
+
+b. History expansion has a new `G' modifier equivalent to the BSD csh `g'
+ modifier, which performs a substitution once per word.
+
+c. All non-incremental search operations may now undo the operation of
+ replacing the current line with the history line.
+
+d. The text inserted by an `a' command in vi mode can be reinserted with
+ `.'.
+
+e. New bindable variable, `show-all-if-unmodified'. If set, the readline
+ completer will list possible completions immediately if there is more
+ than one completion and partial completion cannot be performed.
+
+f. There is a new application-callable `free_history_entry()' function.
+
+g. History list entries now contain timestamp information; the history file
+ functions know how to read and write timestamp information associated
+ with each entry.
+
+h. Four new key binding functions have been added:
+
+ rl_bind_key_if_unbound()
+ rl_bind_key_if_unbound_in_map()
+ rl_bind_keyseq_if_unbound()
+ rl_bind_keyseq_if_unbound_in_map()
+
+------------------------------------------------------------------------------
This document details the changes between this version, bash-2.05b-release,
and the previous version, bash-2.05b-beta2.
f. The history file loading code was changed to allow lines to be saved in
the history list from the shell startup files.
-g. `history -s args' now works bettern in compound commands.
+g. `history -s args' now works better in compound commands.
h. The tilde expansion code was fixed to better recognize when it's being
invoked in an assignment context, which enables expansion after `='
projects / platform / upstream / bash.git / blobdiff