[platform/upstream/bash.git] / CHANGES

This document details the changes between this version, bash-2.02-beta2,
and the previous version, bash-2.02-beta1.

1.  Changes to Bash

a.  A bug was fixed that caused the terminal process group to be set
    incorrectly when performing command substitution of builtins in a
    pipeline.

------------------------------------------------------------------------------
This document details the changes between this version, bash-2.02-beta2,
and the previous version, bash-2.02-beta1.

1.  Changes to Bash

a.  Attempting to `wait' for stopped jobs now generates a warning message.

b.  Pipelines which exit due to SIGPIPE in non-interactive shells are now
    not reported if the shell is compiled -DDONT_REPORT_SIGPIPE.

c.  Some changes were made to builtins/psize.sh and support/bashbug.sh to
    attempt to avoid some /tmp file races and surreptitious file
    substitutions.

d.  Fixed a bug that caused the shell not to compile if configured with
    dparen arithmetic but without aliases.

e.  Fixed a bug that caused the input stream to be switched when assigning
    empty arrays with `bash -c'.

f.  A bug was fixed in the readline expansion glue code that caused bash to
    dump core when expanding lines with an unclosed single quote.

g.  A fix was made to the `cd' builtin so that using a non-empty directory
    from $CDPATH results in an absolute pathname of the new current working
    directory to be displayed after the current directory is changed.

h.  Fixed a bug in the variable assignment code that caused the shell to
    dump core when referencing an unset variable with `set -u' enabled in
    an assignment statement preceding a command.

i.  Fixed a bug in the exit trap code that caused reserved words to not be
    recognized under certain circumstances.

j.  Fixed a bug in the parameter pattern substitution code so that quote
    removal is performed.

k.  The shell should now configure correctly on Apple Rhapsody systems.

l.  The `kill' builtin now prints a usage message if it is not passed any
    arguments.

------------------------------------------------------------------------------
This document details the changes between this version, bash-2.02-beta1,
and the previous version, bash-2.02-alpha1.

1.  Changes to Bash

a.  A few compilation bugs were fixed in the new extended globbing code.

b.  Executing arithmetic commands now sets the command name to `((' so
    error messages look right.

c.  Fixed some build problems with various configuration options.

d.  The `printf' builtin now aborts immediately if an illegal format
    character is encountered.

e.  The code that creates here-documents now behaves better if the file it's
    trying to create already exists for some reason.

f.  Fixed a problem with the extended globbing code that made patterns like
    `x+*' expand incorrectly.

g.  The prompt string expansion code no longer quotes tildes with backslashes.

h.  The bash getcwd() implementation in lib/sh/getcwd.c now behaves better in
    the presence of lstat(2) failures.

i.  Fixed a bug with strsub() that caused core dumps when executing `fc -s'.

j.  The mail checking code now ensures that it has a valid default mailpath.

k.  A bug was fixed that caused local variables to be unset inappropriately
    when sourcing a script from within another sourced script.

l.  A bug was fixed in the history saving code so that functions are saved
    in the history list correctly if `cmdhist' is enabled, but `lithist'
    is not.

m.  A bug was fixed that caused printf overflows when displaying error
    messages.

n.  It should be easier to build the loadble builtins in examples/loadables,
    though some manual editing of the generated Makefile is still required.

o.  The user's primary group is now always ${GROUPS[0]}.

p.  Some updates were made to support/config.guess from the GNU master copy.

q.  Some changes were made to the autoconf support for Solaris 2.6 large
    files.

r.  The `command' builtins now does the right thing when confstr(3) cannot
    find a value for _CS_PATH.

s.  Extended globbing expressions like `*.!(c)' are not history expanded if
    `extglob' is enabled.

t.  Using the `-P' option to `cd' will force the value that is assigned to
    PWD to not contain any symbolic links.

2.  Changes to Readline

a.  The code that prints completion listings now behaves better if one or
    more of the filenames contains non-printable characters.

b.  The time delay when showing matching parentheses is now 0.5 seconds.

------------------------------------------------------------------------------
This document details the changes between this version, bash-2.02-alpha1,
and the previous version, bash-2.01.1-release.

1.  Changes to Bash

a.  OS-specific configuration changes for:  BSD/OS 3.x, Minix 2.x,
    Solaris 2.6, SINIX SVR4.

b.  Changes were made to the generated `info' files so that `install-info'
    works correctly.

c.  PWD is now auto-exported.

d.  A fix was made to the pipeline code to make sure that the shell forks
    to execute simple commands consisting solely of assignment statements.

e.  Changes to the test suite for systems with 14-character filenames.

f.  The default sizes of some internal hash tables have been made smaller
    to reduce the shell's memory footprint.

g.  The `((...))' arithmetic command is now executed directly instead of
    being translated into `let "..."'.

h.  Fixes were made to the expansion code so that "$*", "$@", "${array[@]}",
    and "${array[@]}" expand correctly when IFS does not contain a space
    character, is unset, or is set to NULL.

i.  The indirect expansion code (${!var}) was changed so that the only
    valid values of `var' are variable names, positional parameters, `#',
    `@', and `*'.

j.  An arithmetic expression error in a $((...)) expansion now causes a
    non-interactive shell running in posix mode to exit.

k.  Compound array assignment now splits the words within the parentheses
    on shell metacharacters like the parser would before expansing them
    and performing the assignment.  This is for compatibility with ksh-93.

l.  The internal shell backslash-quoting code (used in the output of `set'
    and completion) now quotes tildes if they appear at the start of the
    string or after a `=' or `:'.

m.  A couple of bugs with `shopt -o' were fixed.

n.  `bash +o' now displays the same output as `set +o' before starting an
    interactive shell.

o.  A bug that caused command substitution and the `eval' builtin to
    occasionally free memory twice when an error was encountered was fixed.

p.  The filename globbing code no longer requires read permission for a
    directory when the filename to be matched does not contain any globbing
    characters, as POSIX.2 specifies.

q.  A bug was fixed so that the job containing the last asynchronous
    process is not removed from the job table until a `wait' is executed
    for that process or another asynchronous process is started.  This
    satisfies a POSIX.2 requirement.

r.  A `select' bug was fixed so that a non-numeric user response is treated
    the same as a numeric response that is out of range.

s.  The shell no longer parses the value of SHELLOPTS from the environment
    if it is restricted, running setuid, or running in `privileged mode'.

t.  Fixes were made to enable large file support on systems such as
    Solaris 2.6, where the size of a file may be larger than can be held
    in an `int'.

u.  The filename hashing code was fixed to not add `./' to the beginning of
    filenames which already begin with `./'.

v.  The configure script was changed so that the GNU termcap library is not
    compiled in if `prefer-curses' has been specified.

w.  HISTCONTROL and HISTIGNORE are no longer applied to the second and
    subsequent lines of a multi-line command.

x.  A fix was made to `disown' so that it does a better job of catching
    out-of-range jobs.

y.  Non-interactive shells no longer report the status of processes terminated
    due to SIGINT, even if the standard output is a terminal.

z.  A bug that caused the output of `jobs' to have extra carriage returns
    was fixed.

aa. A bug that caused PIPESTATUS to not be set when builtins or shell
    functions were executed in the foreground was fixed.

bb. Bash now attempts to detect when it is being run by sshd, and treats
    that case identically to being run by rshd.

cc. A bug that caused `set -a' to export SHELLOPTS when one of the shell
    options was changed was fixed.

dd. The `kill' builtin now disallows empty or missing process id arguments
    instead of treating them as identical to `0', which means the current
    process.

ee. `var=value declare -x var' now behaves identically to
    `var=value export var'.  Similarly for `var=value declare -r var' and
    `var=value readonly var'.

ff. A few memory leaks were fixed.

gg. `alias' and `unalias' now print error messages when passed an argument
    that is not an alias for printing or deletion, even when the shell is
    not interactive, as POSIX.2 specifies.

hh. `alias' and `alias -p' now return a status of 0 when no aliases are
    defined, as POSIX.2 specifes.

ii. `cd -' now prints the pathname of the new working directory if the shell
    is interactive.

jj. A fix was made so that the code that binds $PWD now copes with getcwd()
    returning NULL.

kk. `unset' now checks whether or not a function name it's trying to unset
    is a valid shell identifier only when the shell is running in posix mode.

ll. A change was made to the code that generates filenames for here documents
    to make them less prone to name collisions.

mm. The parser was changed so that `time' is recognized as a reserved word
    only at the beginning of a pipeline.

nn. The pathname canonicalization code was changed so that `//' is converted
    into `/', but all other pathnames beginning with `//' are left alone, as
    POSIX.2 specifies.

oo. The `logout' builtin will no longer exit a non-interactive non-login
    shell.

2.  Changes to Readline

a.  Fixed a problem in the readline test program rltest.c that caused a core
    dump.

b.  The code that handles parser directives in inputrc files now displays
    more error messages.

c.  The history expansion code was fixed so that the appearance of the
    history comment character at the beginning of a word inhibits history
    expansion for that word and the rest of the input line.

3.  New Features in Bash

a.  A new version of malloc, based on the older GNU malloc, that has many
    changes, is more page-based, is more conservative with memory usage,
    and does not `orphan' large blocks when they are freed.

b.  A new version of gmalloc, based on the old GLIBC malloc, with many
    changes and range checking included by default.

c.  A new implementation of fnmatch(3) that includes full POSIX.2 Basic
    Regular Expression matching, including character classes, collating
    symbols, equivalence classes, and support for case-insensitive pattern
    matching.

d.  ksh-88 egrep-style extended pattern matching ([@+*?!](patlist)) has been
    implemented, controlled by a new `shopt' option, `extglob'.

e.  There is a new ksh-like `[[' compound command, which implements
    extended `test' functionality.

f.  There is a new `printf' builtin, implemented according to the POSIX.2
    specification.

g.  There is a new feature for command substitution: $(< filename) now expands
    to the contents of `filename', with any trailing newlines removed
    (equivalent to $(cat filename)).

h.  There are new tilde prefixes which expand to directories from the
    directory stack.

i.  There is a new `**' arithmetic operator to do exponentiation.

j.  There are new configuration options to control how bash is linked:
    `--enable-profiling', to allow bash to be profiled with gprof, and
    `--enable-static-link', to allow bash to be linked statically.

k.  There is a new configuration option, `--enable-cond-command', which
    controls whether or not the `[[' command is included.  It is on by
    default.

l.  There is a new configuration option, `--enable-extended-glob', which
    controls whether or not the ksh extended globbing feature is included.
    It is enabled by default.

m.  There is a new configuration #define in config.h.top that, when enabled,
    will cause all login shells to source /etc/profile and one of the user-
    specific login shell startup files, whether or not the shell is
    interactive.

n.  There is a new invocation option, `--dump-po-strings', to dump
    a shell script's translatable strings ($"...") in GNU `po' format.

o.  There is a new `shopt' option, `nocaseglob', to enable case-insensitive
    pattern matching when globbing filenames and using the `case' construct.

p.  There is a new `shopt' option, `huponexit', which, when enabled, causes
    the shell to send SIGHUP to all jobs when an interactive login shell
    exits.

q.  `bind' has a new `-u' option, which takes a readline function name as an
    argument and unbinds all key sequences bound to that function in a
    specified keymap.

r.  `disown' now has `-a' and `-r' options, to limit operation to all jobs
    and running jobs, respectively.

s.  The `shopt' `-p' option now causes output to be displayed in a reusable
    format.

t.  `test' has a new `-N' option, which returns true if the filename argument
    has been modified since it was last accessed.

u.  `umask' now has a `-p' option to print output in a reusable format.

v.  A new escape sequence, `\xNNN', has been added to the `echo -e' and $'...'
    translation code.  It expands to the character whose ascii code is NNN
    in hexadecimal.

w.  The prompt string expansion code has a new `\r' escape sequence.

x.  The shell may now be cross-compiled for the CYGWIN32 environment on
    a Unix machine.

4.  New Features in Readline

a.  There is now an option for `iterative' yank-last-arg handline, so a user
    can keep entering `M-.', yanking the last argument of successive history
    lines.

b.  New variable, `print-completions-horizontally', which causes completion
    matches to be displayed across the screen (like `ls -x') rather than up
    and down the screen (like `ls').

c.  New variable, `completion-ignore-case', which causes filename completion
    and matching to be performed case-insensitively.

d.  There is a new bindable command, `magic-space', which causes history
    expansion to be performed on the current readline buffer and a space to
    be inserted into the result.

e.  There is a new bindable command, `menu-complete', which enables tcsh-like
    menu completion (successive executions of menu-complete insert a single
    completion match, cycling through the list of possible completions).

f.  There is a new bindable command, `paste-from-clipboard', for use on Win32
    systems, to insert the text from the Win32 clipboard into the editing
    buffer.

g.  The key sequence translation code now understands printf-style backslash
    escape sequences, including \NNN octal escapes.  These escape sequences
    may be used in key sequence definitions or macro values.

h.  An `$include' inputrc file parser directive has been added.

------------------------------------------------------------------------------
This document details the changes between this version, bash-2.01.1-release,
and the previous version, bash-2.01-release.

1.  Changes to Bash

a.  The select command was fixed to check the validity of the user's
    input more strenuously.

b.  A bug was fixed that prevented `time' from timing commands correctly
    when supplied as an argument to `bash -c'.

c.  A fix was made to the mail checking code to keep from adding the same
    mail file to the list of files to check multiple times when parsing
    $MAILPATH.

d.  Fixed an off-by-one error in the tilde expansion library.

e.  When using the compound array assignment syntax, the old value of
    the array is cleared before assigning the new value.

f.  Fixed a bug that could cause a core dump when a trap handler was reset
    to the default in the trap command associated with that signal.

g.  Fixed a bug in the locale code that occurred when assigning a value
    to LC_ALL.

h.  A change was made to the parser so that words of the form xxx=(...)
    are not considered compound assignment statements unless there are
    characters before the `='.

i.  A fix was made to the command tracing code to correctly quote each
    word of output.

j.  Some changes were made to the bash-specific autoconf tests to make them
    more portable.

k.  Completion of words with globbing characters now correctly quotes the
    result.

l.  The directory /var/spool/mail is now preferred to /usr/spool/mail when
    configure is deciding on the default mail directory.

m.  The brace completion code was fixed to not quote the `{' and `}'.

n.  Some fixes were made to make $RANDOM more random in subshells.

o.  System-specific changes were made to configure for: SVR4.2

p.  Changes were made so that completion of words containing globbing chars
    substitutes the result only if a single filename was matched.

q.  The window size is now recomputed after a job is stopped with SIGTSTP if
    the user has set `checkwinsize' with `shopt'.

r.  When doing substring expansion, out-of-range substring specifiers now
    cause nothing to be substituted rather than an expansion error.

s.  A fix was made so that you can no longer trap `SIGEXIT' or `SIGDEBUG' --
    only `EXIT' and `DEBUG' are accepted.

t.  The display of trapped signals now uses the signal number if signals
    for which bash does not know the name are trapped.

u.  A fix was made so that `bash -r' does not turn on restricted mode until
    after the startup files are executed.

v.  A bug was fixed that occasionally caused a core dump when a variable
    found in the temporary environment of export/declare/readonly had a
    null value.

w.  A bug that occasionally caused unallocated memory to be passed to free()
    when doing arithmetic substitution was fixed.

x.  A bug that caused a buffer overrun when expanding a prompt string
    containing `\w' and ${#PWD} exceeded PATH_MAX was fixed.

y.  A problem with the completion code that occasionally caused it to
    refer to a character before the beginning of the readline line buffer
    was fixed.

z.  A bug was fixed so that the `read' builtin restarts reads when
    interrupted by signals other than SIGINT.

aa. Fixed a bug that caused a command to be freed twice when there was
    an evaluation error in the `eval' command.

2.  Changes to Readline

a.  Added a missing `extern' to a declaration in readline.h that kept
    readline from compiling cleanly on some systems.

b.  The history file is now opened with mode 0600 when it is written for
    better security.

c.  Changes were made to the SIGWINCH handling code so that prompt redisplay
    is done better.

d.  ^G now interrupts incremental searches correctly.

e.  A bug that caused a core dump when the set of characters to be quoted
    when completing words was empty was fixed.

------------------------------------------------------------------------------
This document details the changes between this version, bash-2.01-release,
and the previous version, bash-2.01-beta2.

1.  Changes to Bash

a.  The `distclean' target should remove the `printenv' executable if it
    has been created.

b.  The test suite was changed slightly to ensure that the error messages
    are printed in English.

c.  A bug that caused the shell to dump core when a filename containing a
    `/' was passed to `hash' was fixed.

d.  Pathname canonicalization now leaves a leading `//' intact, as POSIX.1
    requires.

e.  A memory leak when completing commands was fixed.

f.  A memory leak that occurred when checking the hash table for commands
    with relative paths was fixed.

------------------------------------------------------------------------------
This document details the changes between this version, bash-2.01-beta2,
and the previous version, bash-2.01-beta1.

1.  Changes to Bash

a.  The `ulimit' builtin translates RLIM_INFINITY to the hard limit only if
    the current (soft) limit is less than or equal to the hard limit.

b.  Fixed a bug that caused the bash emulation of strcasecmp to produce
    incorrect results.

c.  A bug that caused memory to be freed twice when a trap handler resets
    the trap more than once was fixed.

d.  A bug that caused machines where sizeof (pointer) > sizeof (int) to
    fail (and possibly dump core) when trying to unwind-protect a null
    pointer was fixed.

e.  The startup files should not be run with job control enabled.  This fix
    allows SIGINT to once again interrupt startup file execution.

f.  Bash should not change the SIGPROF handler if it is set to something
    other than SIG_DFL.

g.  The completion code that provides bash-specific completions for readline
    now quotes characters that the readline code would treat as word break
    characters if they appear in a file name.

h.  The completion code now correctly quotes filenames containing a `!',
    even if the user attempted to use double quotes when attempting
    completion.

i.  A bug that caused the shell to dump core when `disown' was called without
    arguments and there was no current job was fixed.

j.  A construct like $((foo);bar) is now processed as a command substitution
    rather than as a bad arithmetic substitution.

k.  A couple of bugs that caused `fc' to not obey the `cmdhist' and `lithist'
    shell options when editing and re-executing a series of commands were
    fixed.

l.  A fix was made to the grammar -- the list of commands between `do' and
    `done' in the body of a `for' command should be treated the same as a
    while loop.

2.  Changes to Readline

a.  A couple of bugs that caused the history search functions to attempt to
    free a NULL pointer were fixed.

b.  If the C library provides setlocale(3), readline does not need to look
    at various environment variables to decide whether or not to go into
    eight-bit mode automatically -- just check whether the current locale
    is not `C' or `POSIX'.

c.  If the filename completion function finds that a directory was not closed
    by a previous (interrupted) completion, it closes the directory with
    closedir().

3.  New Features in Bash

a.  New bindable readline commands:  history-and-alias-expand-line and
    alias-expand-line.  The code was always in there, there was just no
    way to execute it.

------------------------------------------------------------------------------
This document details the changes between this version, bash-2.01-beta1,
and the previous version, bash-2.01-alpha1.

1.  Changes to Bash

a.  Fixed a problem that could cause file descriptors used for process
    substitution to conflict with those used explicitly in redirections.

b.  Made it easier to regenerate configure if the user changes configure.in.

c.  ${GROUPS[0]} should always be the primary group, even on systems without
    multiple groups.

d.  Spelling correction is no longer enabled by default.

e.  Fixes to quoting problems in `bashbug'.

f.  OS-specific configuration changes were made for: Irix 6.

g.  OS-specific code changes were made for: QNX.

h.  A more meaningful message is now printed when the file in /tmp for a
    here document cannot be created.

i.  Many changes to the shell's variable initialization code to speed
    non-interactive startup.

j.  Changes to the non-job-control code so that it does not try to open
    /dev/tty.

k.  The output of `set' and `export' is once again sorted, as POSIX wants.

l.  Fixed a problem caused by a recursive call reparsing the value of
    $SHELLOPTS.

m.  The tilde code no longer calls getenv() when it's compiled as part of
    the shell, which should eliminate problems on systems that cannot
    redefine getenv(), like the NeXT OS.

n.  Fixed a problem that caused `bash -o' or `bash +o' to not list all
    the shell options.

o.  Fixed `ulimit' to convert RLIM_INFINITY to the appropriate hard limit
    only if the hard limit is greater than the current (soft) limit.

p.  Fixed a problem that arose when building bash in a different directory
    than the source and y.tab.[ch] were remade with something other than
    bison.  This came up most often on NetBSD.

q.  Fixed a problem with completion -- it thought that `pwd`/[TAB] indicated
    an unfinished command completion (`/), which generated errors.

r.  The bash special tilde expansions (~-, ~+) are now attempted before
    calling the standard tilde expansion code, which should eliminate the
    problems people have been seeing with this on Solaris 2.5.1.

s.  Added support for <stdarg.h> to places where it was missing.

t.  Changed the code that reads the output of a command substitution to not
    go through stdio.  This reduces the memory requirements and is faster.

u.  A number of changes to speed up export environment creation were made.

v.  A number of memory leaks were fixed as the result of running the test
    scripts through Purify.

w.  Fixed a bug that caused subshells forked to interpret executable
    scripts without a leading `#!' to not reinitialize the values of
    the shell options.

2.  Changes to Readline

a.  History library has less `#ifdef SHELL' code -- abstracted stuff out
    into application-specific function hooks.

b.  Readline no longer calls getenv() if it's compiled as part of the shell,
    which should eliminate problems on systems that cannot redefine getenv(),
    like the NeXT OS.

c.  Fixed translation of ESC when `untranslating' macro values.

d.  The region kill operation now fixes the mark if it ends up beyond the
    boundaries of the line after the region is deleted.

3.  New Features in Bash

a.  New argument for `configure':  `--with-curses'.  This can be used to
    override the selection of the termcap library on systems where it is
    deficient.

------------------------------------------------------------------------------
This document details the changes between this version, bash-2.01-alpha1,
and the previous version, bash-2.0-release.

1.  Changes to Bash

a.  System-specific configuration changes for: FreeBSD, SunOS4, Irix,
    MachTen, QNX 4.2, Harris Night Hawk, SunOS5.

b.  System-specific code changes were made for: Linux, 4.4 BSD, QNX 4.2,
    HP-UX, AIX 4.2.

c.  A bug that caused the exec builtin to fail because the full pathname of
    the command could not be found was fixed.

d.  The code that performs output redirections is now more resistant to
    race conditions and possible security exploits.

e.  A bug that caused the shell to dump core when performing pattern
    substitutions on variable values was fixed.

f.  More hosts are now recognized by the auto-configuration mechanism
    (OpenBSD, QNX, others).

g.  Assignments to read-only variables that attempt to convert them to
    arrays are now errors.

h.  A bug that caused shell scripts using array assignments in POSIX mode
    to exit after the assignment was performed was fixed.

i.  The substring expansion code is now more careful about running off the
    ends of the expanded variable value.

j.  A bug that caused completion to fail if a backquoted command substitution
    appeared anywhere on the line was fixed.

k.  The `source' builtin no longer turns off history if it has been enabled
    in a non-interactive shell.

l.  A bug that caused the shell to crash when `disown' was given a pid
    instead of a job number was fixed.

m.  The `cd' spelling correction code will not try to change to `.' if no
    directory entries match a single-character argument.

n.  A bad variable name supplied to `declare', `export', or `readonly' no
    longer causes a non-interactive shell in POSIX mode to exit.

o.  Some fixes were made to the test suite to handle peculiarities of
    various Unix versions.

p.  The bash completion code now quotes characters that readline would
    treat as word breaks for completion but are not shell metacharacters.

q.  Bad options supplied at invocation now cause a usage message to be
    displayed.

r.  Fixes were made to the code that handles DEBUG traps so that the trap
    string is not freed inappropriately.

s.  Some changes were made to the bash debugger in examples/bashdb -- it
    should be closer to working now.

t.  A problem that caused the default filename used for mail checking to be
    wrong was fixed.

u.  A fix was made to the `echo' builtin so that NUL characters printed with
    `echo -e' do not cause the output to be truncated.

v.  A fix was made to the job control code so that the shell behaves better
    when monitor mode is enabled in a non-interactive shell.

w.  Bash no longer catches all of the terminating signals in a non-
    interactive shell until a trap is set on EXIT, which should result in
    quicker startup.

x.  A fix was made to the command timing code so that `time' can be used in
    a loop.

y.  A fix was made to the parser so that `((cmd); cmd2)' is now parsed as
    a nested subshell rather than strictly as an (errnoeous) arithmetic
    command.

z.  A fix was made to the globbing code so that it correctly matches quoted
    filenames beginning with a `.'.

aa. A bug in `fc' that caused some multi-line commands to not be stored as
    one command in the history when they were re-executed after editing
    (with `fc -e') was fixed.

bb. The `ulimit' builtin now attempts to catch some classes of integer
    overflows.

cc. The command-oriented-history code no longer attempts to add `;'
    inappropriately when a newline appears while reading a $(...) command
    substitution.

dd. A bug that caused the shell to dump core when `help --' was executed
    was fixed.

ee. A bug that caused the shell to crash when an unset variable appeared
    in the body of a here document after `set -u' had been executed was
    fixed.

ff. Implicit input redirections from /dev/null for asynchronous commands
    are now handled better.

gg. A bug that caused the shell to fail to compile when configured with
    `--disable-readline' was fixed.

hh. The globbing code should now be interruptible.

ii. Bash now notices when the `kill' builtin is used to send SIGCONT to a
    stopped job and adjusts the data structures accordingly, as if `bg' had
    been executed instead.

jj. A bug that caused the shell to crash when mixing calls to `getopts'
    and `shift' on the same set of positional parameters was fixed.

kk. The command printing code now preserves the `-p' flag to `time'.

ll. The command printing code now handles here documents better when there
    are other redirections associated with the command.

mm. The special glibc environment variable (NNN_GNU_nonoption_argv_flags_)
    is no longer placed into the environment of executed commands -- users
    of glibc had too many problems with it.

nn. Reorganized the code that generates signames.h.  The signal_names list
    is now more complete but may be slightly different (SIGABRT is favored
    over SIGIOT, for example).  The preferred signal names are those
    listed in the POSIX.2 standard.

oo. `bashbug' now uses a filename shorter than 14 characters for its
    temporary file, and asks for confirmation before sending the bug
    report.

pp. A bug that caused TAB completion in vi editing mode to not be turned
    off when `set -o posix' was executed or back on when `set +o posix'
    was executed was fixed.

qq. A bug in the brace expansion code that caused brace expansions appearing
    in new-style $(...) command substitutions to be inappropriately expanded
    was fixed.

rr. A bug in the readline hook shell-expand-line that could cause memory to
    be inappropriately freed was fixed.

ss. A bug that caused some arithmetic expressions containing `&&' and `||'
    to be parsed with the wrong precedence has been fixed.

tt. References to unbound variables after `set -u' has been executed now
    cause the shell to exit immediately, as they should.

uu. A bug that caused the shell to exit inappropriately when `set -e' had
    been executed and a command's return status was being inverted with the
    `!' reserved word was fixed.

vv. A bug that could occasionally cause the shell to crash with a
    divide-by-zero error when timing a command was fixed.

ww. A bug that caused parameter pattern substitution to leave stray
    backslashes in the replacement string when the expression is in
    double quotes was fixed.

xx. The `break' and `continue' builtins now break out of all loops when an
    invalid count argument is supplied.

yy. Fixed a bug that caused PATH to be set to the empty string if
    `command -p' is executed with PATH unset.

zz. Fixed `kill -l signum' to print the signal name without the `SIG' prefix,
    as POSIX specifies.

aaa. Fixed a bug that caused the shell to crash while setting $SHELLOPTS
     if there were no shell options set.

bbb. Fixed `export -p' and `readonly -p' so that when the shell is in POSIX
     mode, their output is as POSIX.2 specifies.

ccc. Fixed a bug in `readonly' so that `readonly -a avar=(...)' actually
     creates an array variable.

ddd. Fixed a bug that prevented `time' from correctly timing background
     pipelines.

2.  Changes to Readline

a.  A bug that caused an extra newline to be printed when the cursor was on
    an otherwise empty line was fixed.

b.  An instance of memory being used after it was freed was corrected.

c.  The redisplay code now works when the prompt is longer than the screen
    width.

d.  `dump-macros' is now a bindable name, as it should have been all along.

e.  Non-printable characters are now expanded when displaying macros and
    their values.

f.  The `dump-variables' and `dump-macros' commands now output a leading
    newline if they're called as the result of a key sequence, rather
    than directly by an application.

3.  New Features in Bash

a.  There is a new builtin array variable: GROUPS, the set of groups to which
    the user belongs.  This is used by the test suite.

4.  New Features in Readline

a.  If a key sequence bound to `universal-argument' is read while reading a
    numeric argument started with `universal-argument', it terminates the
    argument but is otherwise ignored.  This provides a way to insert multiple
    instances of a digit string, and is how GNU emacs does it.

------------------------------------------------------------------------------
This document details the changes between this version, bash-2.0-release,
and the previous version, bash-2.0-beta3.

1.  Changes to Bash

a.  Fix to the `getopts' builtin so that it does the right thing when a
    required option argument is not present.

b.  The completion code now updates the common prefix of matched names
    after FIGNORE processing is done, since any names that were removed
    may have changed the common prefix.

c.  Fixed a bug that made messages in MAILPATH entries not work correctly.

d.  Fixed a serious documentation error in the description of the new
    ${parameter:offset[:length]} expansion.

e.  Fixes to make parameter substring expansion ({$param:offset[:length]})
    work when within double quotes.

f.  Fixes to make ^A (CTLESC) survive an unquoted expansion of positional
    parameters.

g.  Corrected a misspelling of `unlimited' in the output of `ulimit'.

h.  Fixed a bug that caused executable scripts without a leading `#!' to
    occasionally pick up the wrong set of positional parameters.

i.  Linux systems now have a working `ulimit -v', using RLIMIT_AS.

j.  Updated config.guess so that many more machine types are recognized.

k.  Fixed a bug with backslash-quoted slashes in the ${param/pat[/sub]}
    expansion.

l.  If the shell is named `-su', and `-c command' is supplied, read and
    execute the login shell startup files even though the shell is not
    interactive.  This is to support the `-' option to `su'.

m.  Fixed a bug that caused core dumps when the DEBUG trap was ignored
    with `trap "" DEBUG' and a shell function was subsequently executed.

n.  Fixed a bug that caused core dumps in the read builtin when IFS was
    set to the null string and the input had leading whitespace.

2.  Changes to Readline

a.  Fixed a bug that caused a numeric argument of 1024 to be ignored when
    inserting text.

b.  Fixed the display code so that the numeric argument is displayed as it's
    being entered.

c.  Fixed the numeric argument reading code so that `M-- command' is
    equivalent to `M--1 command', as the prompt implies.

3.  New Features in Bash

a.  `ulimit' now sets both hard and soft limits and reports the soft limit
    by default (when neither -H nor -S is specified).  This is compatible
    with versions of sh and ksh that implement `ulimit'.

b.  Integer constants have been extended to base 64.

4.  New Features in Readline

a.  The `home' and `end' keys are now bound to beginning-of-line and
    end-of-line, respectively, if the corresponding termcap capabilities
    are present.

------------------------------------------------------------------------------
This document details the changes between this version, bash-2.0-beta3,
and the previous version, bash-2.0-beta2.

1.  Changes to Bash

a.  System-specific changes for: AIX 4.2, SCO 3.2v[45], HP-UX.

b.  When in POSIX mode, variable assignments preceding a special builtin
    persist in the shell environment after the builtin completes.

c.  Changed all calls to getwd() to getcwd().  Improved check for systems
    where the libc getcwd() calls popen(), since that breaks on some
    systems when job control is being used.

d.  Fixed a bug that caused seg faults when executing scripts with the
    execute bit set but without a leading `#!'.

e.  The environment passed to executed commands is never sorted.

f.  A bug was fixed in the code that expands ${name[@]} to the number of
    elements in an array variable.

g.  A bug was fixed in the array compound assignment code ( A=( ... ) ).

h.  Window size changes now correctly propagate down to readline if
    the shopt `checkwinsize' option is enabled.

i.  A fix was made in the code that expands to the length of a variable
    value (${#var}).

j.  A fix was made to the command builtin so that it did not turn on the
    `no fork' flag inappropriately.

k.  A fix was made to make `set -n' work more reliably.

l.  A fix was made to the job control initialization code so that the
    terminal process group is set to the shell's process group if the
    shell changes its own process group.

2.  Changes to Readline

a.  System-specific changes for: SCO 3.2v[45].

b.  The behavior of the vi-mode `.' when redoing an `i' command was changed
    to insert the text previously inserted by the `i' command rather than
    simply entering insert mode.

3.  New features in Bash

a.  There is a new version of the autoload function package, in
    examples/functions/autoload.v2, that uses arrays and provides more
    functionality.

b.  Support for LC_COLLATE and locale-specific sorting of the results of
    pathname expansion if strcoll() is available.

4.  New Features in Readline

a.  Support for locale-specific sorting of completion possibilities if
    strcoll() is available.

------------------------------------------------------------------------------
This document details the changes between this version, bash-2.0-beta2,
and the previous version, bash-2.0-beta1.

1.  Changes to Bash

a.  `pushd -' is once again equivalent to `pushd $OLDPWD'.

b.  OS-specific changes for: SCO 3.2v[45].

c.  A change was made to the fix for the recently-reported security hole
    when reading characters with octal value 255 to make it work better on
    systems with restartable system calls when not using readline.

d.  Some changes were made to the test suite so that it works if you
    configure bash with --enable-usg-echo-default.

e.  A fix was made to the parsing of conditional arithmetic expressions.

f.  Illegal arithmetic bases now cause an arithmetic evaluation error rather
    than being silently reset.

g.  Multiple arithmetic bases now cause an arithmetic evaluation error
    instead of being ignored.

h.  A fix was made to the evaluation of ${param?word} to conform to POSIX.2.

i.  A bug that sometimes caused array indices to be evaluated twice (which
    would cause errors when they contained assignment statements) was fixed.

j.  `ulimit' was rewritten to avoid problems with getrlimit(2) returning
    unsigned values and to simplify the code.

k.  A bug in the command-oriented-history code that caused it to sometimes
    put semicolons after right parens inappropriately was fixed.

l.  The values inserted into the prompt by the \w and \W escape sequences
    are now quoted to prevent further expansion.

m.  An interactive shell invoked as `sh' now reads and executes commands
    from the file named by $ENV when it starts up.  If it's a login shell,
    it does this after reading /etc/profile and ~/.profile.

n.  The file named by $ENV is never read by non-interactive shells.

2.  Changes to Readline

a.  A few changes were made to hide some macros and functions that should not
    be public.

b.  An off-by-one error that caused seg faults in the history expansion code
    was fixed.

3.  New Features in Bash

a.  The ksh-style ((...)) arithmetic command was implemented.  It is exactly
    identical to let "...".  This is controlled by a new option to configure,
    `--enable-dparen-arithmetic', which is on by default.

b.  There is a new #define available in config.h.top: SYS_BASH_LOGOUT.  If
    defined to a filename, bash reads and executes commands from that file
    when a login shell exits.  It's commented out by default.

c.  `ulimit' has a `-l' option that reports the maximum amount of data that
    may be locked into memory on 4.4BSD-based systems.

------------------------------------------------------------------------------
This document details the changes between this version, bash-2.0-beta1,
and the previous version, bash-2.0-alpha4.

1.  Changes to Bash

a.  A bug that sometimes caused traps to be ignored on signals the
    shell treats specially was fixed.

b.  The internationalization code was changed to track the values of
    LC_* variables and call setlocale() as appropriate.  The TEXTDOMAIN
    and TEXTDOMAINDIR variables are also tracked; changes cause calls
    to textdomain() and bindtextdomain(), if available.

c.  A bug was fixed that sometimes caused double-quoted strings to be
    parsed incorrectly.

d.  Changes were made so that the siglist code compiles correctly on
    Solaris 2.5.

e.  Added `:' to the set of characters that cause word breaks for the
    completion code so that pathnames in assignments to $PATH can be
    completed.

f.  The `select' command was fixed to print $PS3 to stderr.

g.  Fixed an error in the manual page section describing the effect that
    setting and unsetting GLOBIGNORE has on the setting of the `dotglob'
    option.

h.  The time conversion code now uses CLK_TCK rather than CLOCKS_PER_SEC
    on systems without gettimeofday() and resources.

i.  The getopt static variables are now initialized each time a subshell
    is started, so subshells using `getopts' work right.

j.  A sign-extension bug that caused a possible security hole was fixed.

k.  The parser now reads characters between backquotes within a double-
    quoted string as a single word, so double quotes in the backquoted
    string don't terminate the enclosing double-quoted string.

l.  A bug that caused `^O' to work incorrectly when typed as the first
    thing to an interactive shell was fixed.

m.  A rarely-exercised off-by-one error in the code that quotes variable
    values was fixed.

n.  Some memory and file descriptor leaks encountered when running a
    shell script that is executable but does not have a leading `#!'
    were plugged.

2.  Changes to Readline

a.  A bug that sometimes caused incorrect results when trying to read
    typeahead on systems without FIONREAD was fixed.

3.  New Features in Bash

a.  The command timing code now uses the value of the TIMEFORMAT variable
    to format and display timing statistics.

b.  The `time' reserved word now accepts a `-p' option to force the
    POSIX.2 output format.

c.  There are a couple of new and updated scripts to convert csh startup
    files to bash format.

d.  There is a new builtin array variable: BASH_VERSINFO.  The various
    members hold the parts of the version information in BASH_VERSION,
    plus the value of MACHTYPE.

4.  New Features in Readline

a.  Setting LANG to `en_US.ISO8859-1' now causes readline to enter
    eight-bit mode.

------------------------------------------------------------------------------
This document details the changes between this version, bash-2.0-alpha4,
and the previous version, bash-2.0-alpha3.

1.  Changes to Bash

a.  There is better detection of rsh connections on Solaris 2.

b.  Assignments to read-only variables preceding a command name are now
    variable assignment errors.  Variable assignment errors cause
    non-interactive shells running in posix mode to exit.

c.  The word tokenizer was rewritten to handle nested quotes and pairs
    ('', "", ``, ${...}, $(...), $[...], $'...', $"...", <(...), >(...))
    correctly.  Some of the parameter expansion code was updated as a
    consequence.

d.  A fix was made to `test' when given three arguments so that a binary
    operator is checked for first, before checking that the first argument
    is `!'.

e.  2''>/dev/null is no longer equivalent to 2>/dev/null.

f.  Parser error messages were regularized, and in most cases the name of
    the shell script being read by a non-interactive shell is not printed
    twice.

g.  A fix was made to the completion code so that it no longer removes the
    text the user typed in some cases.

h.  The special glibc `getopt' environment variable is no longer put into
    the environment on machines with small values of ARG_MAX.

i.  The expansion of ${...} now follows the POSIX.2 rules for finding the
    closing `}'.

j.  The shell no longer displays spurious status messages for background
    jobs in shell scripts that complete successfully when the script is
    run from a terminal.

k.  `shopt -o' now correctly updates $SHELLOPTS.

l.  A bug that caused the $PATH searching code to return a non-executable
    file even when an executable file with the same name appeared later in
    $PATH was fixed.

m.  The shell now does tilde expansions on unquoted `:~' in assignment
    statements when not in posix mode.

n.  Variable assignment errors when a command consists only of assignments
    now cause non-interactive shells to exit when in posix mode.

o.  If the variable in a `for' or `select' command is read-only, or not a
    legal shell identifier, a variable assignment error occurs.

p.  `test' now handles `-a' and `-o' as binary operators when three arguments
    are supplied, and correctly parses `( word )' as equivalent to `word'.

q.  `test' was fixed so that file names of the form /dev/fd/NN mean the same
    thing on all systems, even Linux.

r.  Fixed a bug in the globbing code that caused patterns with multiple
    consecutive `*'s to not be matched correctly.

s.  Fixed a bug that caused $PS2 to not be printed when an interactive shell
    not using readline is reading a here document.

t.  Fixed a bug that caused history expansion to be performed inappropriately
    when a single-quoted string spanned more than one line.

u.  `getopts' now checks that the variable name passed by the user as the
    second argument is a legal shell identifier and that the variable is
    not read-only.

v.  Fixed `getopts' to obey POSIX.2 rules for setting $OPTIND when it
    encounters an error.

w.  Fixed `set' to display variable values in a form that can be re-read.

x.  Fixed a bug in the code that keeps track of whether or not local variables
    have been declared at the current level of function nesting.

y.  Non-interactive shells in posix mode now exit if the name in a function
    declaration is not a legal identifier.

z.  The job control code now ignores stopped children when the shell is not
    interactive.

aa. The `cd' builtin no longer attempts spelling correction on the directory
    name if the shell is not interactive, regardless of the setting of the
    `cdspell' option.

bb. Some OS-specific changes were made for SCO 3.2v[45] and AIX 4.2.

cc. `time' now prints its output to stderr, as POSIX.2 specifies.

2.  Fixes to Readline

a.  After printing possible completions, all lines of a multi-line prompt
    are redisplayed.

b.  Some changes were made to the terminal handling code in rltty.c to
    work around AIX 4.2 bugs.

3.  New Features in Bash

a.  There is a new loadable builtin: sprintf, with calling syntax
                sprintf var format [args]
    This provides an easy way to simulate ksh left- and right-justified
    variable values.

b.  The expansions of \h and \H in prompt strings were swapped.  \h now
    expands to the hostname up to the first `.', as in bash-1.14.

4.  New Features in Readline

a.  The bash-1.14 behavior when ^M is typed while doing an incremental
    search was restored.  ^J may now be used to terminate the search without
    accepting the line.

b.  There is a new bindable variable: disable-completion.  This inhibits
    word completion and causes the completion character to be inserted as
    if it had been bound to self-insert.

------------------------------------------------------------------------------
This document details the changes between this version, bash-2.0-alpha3,
and the previous version, bash-2.0-alpha2.

There is now a file `COMPAT' included in the distribution that lists the
user-visible incompatibilities between 1.14 and 2.0.

1. Changes to Bash

a. Some work was done so that word splitting of the rhs of assignment
   statements conforms more closely to historical practice.

b. A couple of errant memory frees were fixed.

c. A fix was made to the test builtin so it recognizes `<' and `>' as
   binary operators.

d. The GNU malloc in lib/malloc/malloc.c now scrambles memory as it's
   allocated and freed.  This is to catch callers that refer to freed
   memory or assume something about newly-allocated memory.

e. Fixed a problem with conversion to 12-hour time in the prompt
   expansion code.

f. Fixed a problem with configure's argument parsing order.  Now you can
   correctly turn on specific options after using --enable-minimal-config.

g. The configure script now automatically disables the use of GNU malloc
   on systems where it's appropriate (better than having people read the
   NOTES file and do it manually).

h. There are new prompt expansions (\v and \V) to insert version information
   into the prompt strings.

i. The default prompt string now includes the version number.

j. Most of the builtins that take no options were changed to use the
   internal getopt so they can produce proper error messages for -?
   and incorrect options.

k. Some system-specific changes were made for SVR4.2 and Solaris 2.5.

l. Bash now uses PATH_MAX instead of MAXPATHLEN and NAME_MAX instead of
   MAXNAMLEN.

m. A couple of problems caused by uninitialized variables were fixed.

n. There are a number of new loadable builtin examples: logname, basename,
   dirname, tty, pathchk, tee, head, and rmdir.  All of these conform to
   POSIX.2.

o. Bash now notices changes in TZ and calls tzset() if present, so
   changing TZ will alter the time printed by prompt expansions.

p. The source was reorganized a bit so I don't have to wait so long for
   some files to compile, and to facilitate the creation of a `shell
   library' at some future point.

q. Bash no longer turns off job control if called as `sh', since the
   POSIX.2 spec includes job control as a standard feature.

r. `bash -o posix' now works as intended.

s. Fixed a problem with the completion code: when completing a filename
   that contained globbing characters, if show-all-if-ambiguous was set,
   the completion code would remove the user's text.

t. Fixed ulimit so that (hopefully) the full range of limits is available
   on HPUX systems.

u. A new `shopt' option (`hostcomplete') enables and disables hostname
   completion.

v. The shell no longer attempts to save the history on an abort(),
   which is usually called by programming_error().

w. The `-s' option to `fc' was changed to echo the command to be executed
   to stderr instead of stdout.

x. If the editor invoked by `fc -e' exits with a non-zero status, no
   commands are executed.

y. Fixed a bug that made the shopt `histverify' option work incorrectly.

z. There is a new variable `MACHTYPE' whose value is the GNU-style
   `cpu-company-system' system description as set by configure.  (The
   values of MACHTYPE and HOSTTYPE should really be swapped.)

aa. The `ulimit' builtin now allows the maximum virtual memory size to be
    set via setrlimit(2) if RLIMIT_VMEM is defined.

bb. `bash -nc 'command'' no longer runs `command'.

2. Changes to Readline

a. Fixed a typo in the code that checked for FIONREAD in input.c.

b. Fixed a bug in the code that outputs keybindings, so things like C-\
   are quoted properly.

c. Fixed a bug in the inputrc file parsing code to handle the problems
   caused by inputrc files created from the output of `bind -p' in
   previous versions of bash.  The problem was due to the bug fixed
   in item b above.

d. Readline no longer turns off the terminal's meta key, and turns it on
   once the first time it's called.

------------------------------------------------------------------------------
This file documents the changes between this version, bash-2.0-alpha2,
and the previous version, bash-2.0-alpha.

1. Changes to Bash

a. The shell no longer thinks directories are executable.

b. `disown' has a new option, `h', which inhibits the resending of SIGHUP
   but does not remove the job from the jobs table.

c. The varargs functions in error.c now use ANSI-C `stdarg' if available.

d. The build process now treats the `build version' in .build as local to
   the build directory, so different versions built from the same source
   tree have different `build versions'.

e. Some problems with the grammar have been fixed. (It used `list' in a few
   productions where `compound_list' was needed.  A `list' must be terminated
   with a newline or semicolon; a `compound_list' need not be.)

f. A fix was made to keep `wait' from hanging when waiting for all background
   jobs.

g. `bash --help' now writes its output to stdout, like the GNU Coding Standards
   specify, and includes the machine type (the value of MACHTYPE).

h. `bash --version' now prints more information and exits successfully, like
   the GNU Coding Standards specify.

i. The output of `time' and `times' now prints fractional seconds with three
   places after the decimal point.

j. A bug that caused process substitutions to screw up the pipeline printed
   by `jobs' was fixed.

k. Fixes were made to the code that implements $'...' and $"..." so they
   work as documented.

l. The process substitution code now opens named pipes for reading with
   O_NONBLOCK to avoid hanging.

m. Fixes were made to the trap code so the shell cleans up correctly if the
   trap command contains a `return' and we're executing a function or
   sourcing a script with `.'.

n. Fixes to doc/Makefile.in so that it doesn't try to remake all of the
   documentation (ps, dvi, etc.) on a `make install'.

o. Fixed an auto-increment error that caused bash -c args to sometimes dump
   core.

p. Fixed a bug that caused $HISTIGNORE to fail when the history line
   contained globbing characters.

2. Changes to Readline

a. There is a new string variable, rl_library_version, available for use by
   applications.  The current value is "2.1".

b. A bug encountered when expand-tilde was enabled and file completion was
   attempted on a word beginning with `~/' was fixed.

c. A slight change was made to the incremental search termination behavior.
   ESC still terminates the search, but if input is pending or arrives
   within 0.1 seconds (on systems with select(2)), it is used as a prefix
   character.  This is intented to allow users to terminate searches with
   the arrow keys and get the behavior they expect.