-This is the Bash FAQ, version 3.27, for Bash version 3.0.
+This is the Bash FAQ, version 3.32, for Bash version 3.1.
This document contains a set of frequently-asked questions concerning
Bash, the GNU Bourne-Again Shell. Bash is a freely-available command
Section B: The latest version
-B1) What's new in version 3.0?
-B2) Are there any user-visible incompatibilities between bash-3.0 and
- bash-1.14.7?
+B1) What's new in version 3.1?
+B2) Are there any user-visible incompatibilities between bash-3.1 and
+ bash-2.05b?
Section C: Differences from other Unix shells
A2) What's the latest version?
-The latest version is 3.0, first made available on 27 July, 2004.
+The latest version is 3.1, first made available on 09 December, 2005.
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 3.0:
+The following URLs tell how to get version 3.1:
-ftp://ftp.gnu.org/pub/gnu/bash/bash-3.0.tar.gz
-ftp://ftp.cwru.edu/pub/bash/bash-3.0.tar.gz
+ftp://ftp.gnu.org/pub/gnu/bash/bash-3.1.tar.gz
+ftp://ftp.cwru.edu/pub/bash/bash-3.1.tar.gz
Formatted versions of the documentation are available with the URLs:
-ftp://ftp.gnu.org/pub/gnu/bash/bash-doc-3.0.tar.gz
-ftp://ftp.cwru.edu/pub/bash/bash-doc-3.0.tar.gz
+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
+
+Any patches for the current version are available with the URL:
+
+ftp://ftp.cwru.edu/pub/bash/bash-3.1-patches/
A4) On what machines will bash run?
Bash has been ported to versions of Windows implementing the Win32
programming interface. This includes Windows 95 and Windows NT.
-The port was done by Cygnus Solutions as part of their CYGWIN
-project. For more information about the project, look at the URLs
-
-http://www.cygwin.com/
-http://sourceware.cygnus.com/cygwin
+The port was done by Cygnus Solutions (now part of Red Hat) as part
+of their CYGWIN project. For more information about the project, see
+http://www.cygwin.com/.
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 a
-port of bash-2.05 to the CYGWIN environment, and it is available as
-part of their current release.
+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
+being tested and should be available soon.
Bash-2.05b and later versions should require no local Cygnus changes to
build and run under CYGWIN.
Mark began to work with bash-2.05, but I don't know the current status.
Bash-3.0 compiles and runs with no modifications under Microsoft's Services
-for Unix (SFU), once known as Interix.
+for Unix (SFU), once known as Interix. I do not anticipate any problems
+with building bash-3.1.
A6) How can I build bash with gcc?
Section B: The latest version
-B1) What's new in version 3.0?
+B1) What's new in version 3.1?
+
+Bash-3.1 is the first 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).
+
+o Bash-3.1 may now be configured and built in a mode that enforces strict
+ POSIX compliance.
-Bash-3.0 is the third major release of bash. The features introduced
-in the intermediate releases following bash-2.05 have been completed.
-Support for the bash debugger (a separate project) has been integrated.
+o The `+=' assignment operator, which appends to the value of a string or
+ array variable, has been implemented.
-Bash-3.0 contains the following new features (see the manual page for
-complete descriptions and the CHANGES and NEWS files in the bash-3.0
-distribution):
+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
is a new `extdebug' option to turn the non-default options on
o The `gettext' package and libintl have been integrated, and the shell
messages may be translated into other languages
-A short feature history dating from Bash-2.0:
-
Bash-2.05b introduced the following new features:
o support for multibyte characters has been added to both bash and readline
lots of code now smaller and faster
test suite greatly expanded
-B2) Are there any user-visible incompatibilities between bash-3.0 and
- bash-1.14.7?
+B2) Are there any user-visible incompatibilities between bash-3.1 and
+ bash-2.05b?
-There are a few incompatibilities between version 1.14.7 and version 3.0.
+There are a few incompatibilities between version 2.05b and version 3.1.
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.
case-insensitive pattern matching and globbing
variable assignments preceding commands affect only that command,
even for builtins and functions
- posix mode
+ posix mode and strict posix conformance
redirection to /dev/fd/N, /dev/stdin, /dev/stdout, /dev/stderr,
/dev/tcp/host/port, /dev/udp/host/port
debugger support, including `caller' builtin and new variables
RETURN trap
+ the `+=' assignment operator
Things sh has that bash does not:
RETURN trap
Timestamps in history entries
{x..y} brace expansion
+ The `+=' assignment operator
Things ksh88 has or uses that bash does not:
tracked aliases (alias -t)
`fc' has been renamed to `hist'
`.' can execute shell functions
exit statuses between 0 and 255
- `+=' variable assignment operator
FPATH and PATH mixing
getopts -a
-I invocation option
command name completion
ENV processed only for interactive shells
set -o pipefail
+ The `+=' assignment operator
Section D: Why does bash do some things differently than other Unix shells?
will print `Broken pipe' to stderr when ps is killed by a
SIGPIPE.
-You can build a version of bash that will not report SIGPIPE errors
-by uncommenting the definition of DONT_REPORT_SIGPIPE in the file
-config-top.h.
+As of bash-3.1, bash will 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
wrap lines at the wrong column?
into a `while' loop that repeatedly calls `read' will result in
the same behavior.
-Each element of a pipeline runs in a separate process, a child of
-the shell running the pipeline. A subprocess cannot affect its
-parent's environment. When the `read' command sets the variable
-to the input, that variable is set only in the subshell, not the
-parent shell. When the subshell exits, the value of the variable
-is lost.
+Each element of a pipeline, even a builtin or shell function,
+runs in a separate process, a child of the shell running the
+pipeline. A subprocess cannot affect its parent's environment.
+When the `read' command sets the variable to the input, that
+variable is set only in the subshell, not the parent shell. When
+the subshell exits, the value of the variable is lost.
Many pipelines that end with `read variable' can be converted
into command substitutions, which will capture the output of
breaking some of the shell functionality into embeddable libraries
a module system like zsh's, using dynamic loading like builtins
-date-stamped command history
a bash programmer's guide with a chapter on creating loadable builtins
a better loadable interface to perl with access to the shell builtins and
variables (contributions gratefully accepted)
ksh93-like `nameref' variables
-ksh93-like `+=' variable assignment operator
ksh93-like `xx.yy' variables (including some of the .sh.* variables) and
associated disipline functions
Some of the new ksh93 pattern matching operators, like backreferencing
H5) When will the next release appear?
-The next version will appear sometime in 2005. Never make predictions.
+The next version will appear sometime in 2006. Never make predictions.
-This document is Copyright 1995-2004 by Chester Ramey.
+This document is Copyright 1995-2005 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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