-This is the Bash FAQ, version 3.32, for Bash version 3.1.
+This is the Bash FAQ, version 3.34, for Bash version 3.2.
This document contains a set of frequently-asked questions concerning
Bash, the GNU Bourne-Again Shell. Bash is a freely-available command
of FAQ articles periodically posted to comp.unix.shell.
Questions and comments concerning this document should be sent to
-chet@po.cwru.edu.
+chet.ramey@case.edu.
This document is available for anonymous FTP with the URL
Section B: The latest version
-B1) What's new in version 3.1?
-B2) Are there any user-visible incompatibilities between bash-3.1 and
+B1) What's new in version 3.2?
+B2) Are there any user-visible incompatibilities between bash-3.2 and
bash-2.05b?
Section C: Differences from other Unix shells
E11) If I resize my xterm while another program is running, why doesn't bash
notice the change?
E12) Why don't negative offsets in substring expansion work like I expect?
+E13) Why does filename completion misbehave if a colon appears in the filename?
Section F: Things to watch out for on certain Unix versions
A2) What's the latest version?
-The latest version is 3.1, first made available on 09 December, 2005.
+The latest version is 3.2, first made available on 12 October, 2006.
A3) Where can I get it?
Bash is the GNU project's shell, and so is available from the
master GNU archive site, ftp.gnu.org, and its mirrors. The
latest version is also available for FTP from ftp.cwru.edu.
-The following URLs tell how to get version 3.1:
+The following URLs tell how to get version 3.2:
-ftp://ftp.gnu.org/pub/gnu/bash/bash-3.1.tar.gz
-ftp://ftp.cwru.edu/pub/bash/bash-3.1.tar.gz
+ftp://ftp.gnu.org/pub/gnu/bash/bash-3.2.tar.gz
+ftp://ftp.cwru.edu/pub/bash/bash-3.2.tar.gz
Formatted versions of the documentation are available with the URLs:
-ftp://ftp.gnu.org/pub/gnu/bash/bash-doc-3.1.tar.gz
-ftp://ftp.cwru.edu/pub/bash/bash-doc-3.1.tar.gz
+ftp://ftp.gnu.org/pub/gnu/bash/bash-doc-3.2.tar.gz
+ftp://ftp.cwru.edu/pub/bash/bash-doc-3.2.tar.gz
Any patches for the current version are available with the URL:
-ftp://ftp.cwru.edu/pub/bash/bash-3.1-patches/
+ftp://ftp.cwru.edu/pub/bash/bash-3.2-patches/
A4) On what machines will bash run?
Cygnus originally ported bash-1.14.7, and that port was part of their
early GNU-Win32 (the original name) releases. Cygnus has also done
ports of bash-2.05b and bash-3.0 to the CYGWIN environment, and both
-are available as part of their current release. Bash-3.1 is currently
+are available as part of their current release. Bash-3.2 is currently
being tested and should be available soon.
Bash-2.05b and later versions should require no local Cygnus changes to
Bash-3.0 compiles and runs with no modifications under Microsoft's Services
for Unix (SFU), once known as Interix. I do not anticipate any problems
-with building bash-3.1.
+with building bash-3.1 or bash-3.2.
A6) How can I build bash with gcc?
Section B: The latest version
-B1) What's new in version 3.1?
+B1) What's new in version 3.2?
-Bash-3.1 is the first maintenance release of the third major release of
+Bash-3.2 is the second maintenance release of the third major release of
bash. It contains the following significant new features (see the manual
page for complete descriptions and the CHANGES and NEWS files in the
-bash-3.1 distribution).
+bash-3.2 distribution).
+
+o Bash-3.2 now checks shell scripts for NUL characters rather than non-printing
+ characters when deciding whether or not a script is a binary file.
+
+o Quoting the string argument to the [[ command's =~ (regexp) operator now
+ forces string matching, as with the other pattern-matching operators.
+
+A short feature history dating from Bash-2.0:
+
+Bash-3.1 contained the following new features:
o Bash-3.1 may now be configured and built in a mode that enforces strict
POSIX compliance.
o It is now possible to ignore case when matching in contexts other than
filename generation using the new `nocasematch' shell option.
-A short feature history dating from Bash-2.0:
-
Bash-3.0 contained the following new features:
o Features to support the bash debugger have been implemented, and there
lots of code now smaller and faster
test suite greatly expanded
-B2) Are there any user-visible incompatibilities between bash-3.1 and
+B2) Are there any user-visible incompatibilities between bash-3.2 and
bash-2.05b?
-There are a few incompatibilities between version 2.05b and version 3.1.
+There are a few incompatibilities between version 2.05b and version 3.2.
They are detailed in the file COMPAT in the bash distribution. That file
is not meant to be all-encompassing; send mail to bash-maintainers@gnu.org
if if you find something that's not mentioned there.
read -e/-p/-a/-t/-n/-d/-s/-u,
readonly -a/-f/name=value, trap -l, set +o,
set -b/-m/-o option/-h/-p/-B/-C/-H/-P,
- unset -f/-v, ulimit -m/-p/-u,
+ unset -f/-v, ulimit -i/-m/-p/-q/-u/-x,
type -a/-p/-t/-f/-P, suspend -f, kill -n,
test -o optname/s1 == s2/s1 < s2/s1 > s2/-nt/-ot/-ef/-O/-G/-S
bash reads ~/.bashrc for interactive shells, $ENV for non-interactive
set -o braceexpand/-o histexpand/-o interactive-comments/
-o notify/-o physical/-o posix/-o hashall/-o onecmd/
-h/-B/-C/-b/-H/-P, set +o, suspend, trap -l, type,
- typeset -a/-F/-p, ulimit -u, umask -S, alias -p, shopt,
- disown, printf, complete, compgen
+ typeset -a/-F/-p, ulimit -i/-q/-u/-x, umask -S, alias -p,
+ shopt, disown, printf, complete, compgen
`!' csh-style history expansion
POSIX.2-style globbing character classes
POSIX.2-style globbing equivalence classes
C3) Which new features in ksh-93 are not in bash, and which are?
-New things in ksh-93 not in bash-3.0:
+New things in ksh-93 not in bash-3.2:
associative arrays
floating point arithmetic and variables
math library functions
lexical scoping for local variables in `ksh' functions
no scoping for local variables in `POSIX' functions
-New things in ksh-93 present in bash-3.0:
+New things in ksh-93 present in bash-3.2:
[n]<&word- and [n]>&word- redirections (combination dup and close)
for (( expr1; expr2; expr3 )) ; do list; done - arithmetic for command
?:, ++, --, `expr1 , expr2' arithmetic operators
will print `Broken pipe' to stderr when ps is killed by a
SIGPIPE.
-As of bash-3.1, bash will not report SIGPIPE errors by default. You
+As of bash-3.1, bash does not report SIGPIPE errors by default. You
can build a version of bash that will report such errors.
E3) When I have terminal escape sequences in my prompt, why does bash
To use negative offsets that begin with a minus sign, separate the
minus sign and the colon with a space.
+E13) Why does filename completion misbehave if a colon appears in the filename?
+
+Filename completion (and word completion in general) may appear to behave
+improperly if there is a colon in the word to be completed.
+
+The colon is special to readline's word completion code: it is one of the
+characters that breaks words for the completer. Readline uses these characters
+in sort of the same way that bash uses $IFS: they break or separate the words
+the completion code hands to the application-specific or default word
+completion functions. The original intent was to make it easy to edit
+colon-separated lists (such as $PATH in bash) in various applications using
+readline for input.
+
+This is complicated by the fact that some versions of the popular
+`bash-completion' programmable completion package have problems with the
+default completion behavior in the presence of colons.
+
+The current set of completion word break characters is available in bash as
+the value of the COMP_WORDBREAKS variable. Removing `:' from that value is
+enough to make the colon not special to completion:
+
+COMP_WORDBREAKS=${COMP_WORDBREAKS//:}
+
+You can also quote the colon with a backslash to achieve the same result
+temporarily.
+
Section F: Things to watch out for on certain Unix versions
F1) Why can't I use command line editing in my `cmdtool'?
The `set' commands between the single quotes may also be placed
in ~/.inputrc.
+The script examples/scripts.noah/meta.bash encapsulates the bind
+commands in a shell function.
+
G2) How do I write a function `x' to replace builtin command `x', but
still invoke the command from within the function?
Cameron Newham and Bill Rosenblatt have written a book on bash, published
by O'Reilly and Associates. The book is based on Bill Rosenblatt's Korn
Shell book. The title is ``Learning the Bash Shell'', and the ISBN number
-is 1-56592-147-X. Look for it in fine bookstores near you. This book
-covers bash-1.14, but has an appendix describing some of the new features
-in bash-2.0.
-
-A second edition of this book is available, published in January, 1998.
-The ISBN number is 1-56592-347-2. Look for it in the same fine bookstores
-or on the web.
+of the third edition, published in March, 2005, is 0-596-00965-8. Look for
+it in fine bookstores near you. This edition of the book has been updated
+to cover bash-3.0.
The GNU Bash Reference Manual has been published as a printed book by
Network Theory Ltd (Paperback, ISBN: 0-9541617-7-7, Feb 2003). It covers
http://www.network-theory.co.uk/bash/manual/ for details). The publisher
will donate $1 to the Free Software Foundation for each copy sold.
+Arnold Robbins and Nelson Beebe have written ``Classic Shell Scripting'',
+published by O'Reilly. The first edition, with ISBN number 0-596-00595-4,
+was published in May, 2005.
+
+Chris F. A. Johnson, a frequent contributor to comp.unix.shell and
+gnu.bash.bug, has written ``Shell Scripting Recipes: A Problem-Solution
+Approach,'' a new book on shell scripting, concentrating on features of
+the POSIX standard helpful to shell script writers. The first edition from
+Apress, with ISBN number 1-59059-471-1, was published in May, 2005.
+
H3) What's coming in future versions?
These are features I hope to include in a future version of bash.
H5) When will the next release appear?
-The next version will appear sometime in 2006. Never make predictions.
+The next version will appear sometime in 2007. Never make predictions.
-This document is Copyright 1995-2005 by Chester Ramey.
+This document is Copyright 1995-2006 by Chester Ramey.
Permission is hereby granted, without written agreement and
without license or royalty fees, to use, copy, and distribute
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