Chapter 10: Installing Bash

144

--enable-progcomp

Enable the programmable completion facilities (see Section 8.6 [Programmable

Completion], page 124). If Readline is not enabled, this option has no effect.

--enable-prompt-string-decoding

Turn on the interpretation of a number of backslash-escaped characters in the

$PS1, $PS2, $PS3, and $PS4 prompt strings. See Section 6.9 [Controlling the

Prompt], page 92, for a complete list of prompt string escape sequences.

--enable-readline

Include support for command-line editing and history with the Bash version of the Readline library (see Chapter 8 [Command Line Editing], page 101).

--enable-restricted

Include support for a restricted shell. If this is enabled, Bash, when called as rbash, enters a restricted mode. See Section 6.10 [The Restricted Shell], page 93, for a description of restricted mode.

--enable-select

Include the select compound command, which allows the generation of simple menus (see Section 3.2.4.2 [Conditional Constructs], page 10).

--enable-separate-helpfiles

Use external files for the documentation displayed by the help builtin instead of storing the text internally.

--enable-single-help-strings

Store the text displayed by the help builtin as a single string for each help topic. This aids in translating the text to different languages. You may need to disable this if your compiler cannot handle very long string literals.

--enable-strict-posix-default

Make Bash posix-conformant by default (see Section 6.11 [Bash POSIX Mode], page 94).

--enable-usg-echo-default

A synonym for --enable-xpg-echo-default.

--enable-xpg-echo-default

Make the echo builtin expand backslash-escaped characters by default, without requiring the -e option. This sets the default value of the xpg_echo shell option to on, which makes the Bash echo behave more like the version specified in the

Single Unix Specification, version 3. See Section 4.2 [Bash Builtins], page 48, for a description of the escape sequences that echo recognizes.

The file config-top.h contains C Preprocessor ‘#define’ statements for options which are not settable from configure. Some of these are not meant to be changed; beware of the consequences if you do. Read the comments associated with each definition for more information about its effect.

Appendix A: Reporting Bugs

145

Appendix A Reporting Bugs

Please report all bugs you find in Bash. But first, you should make sure that it really is a bug, and that it appears in the latest version of Bash. The latest version of Bash is always available for FTP from ftp://ftp.gnu.org/pub/gnu/bash/.

Once you have determined that a bug actually exists, use the bashbug command to submit a bug report. If you have a fix, you are encouraged to mail that as well! Suggestions and ‘philosophical’ bug reports may be mailed to bug-bash@gnu.org or posted to the Usenet newsgroup gnu.bash.bug.

All bug reports should include:

• The version number of Bash.

• The hardware and operating system.

• The compiler used to compile Bash.

• A description of the bug behaviour.

• A short script or ‘recipe’ which exercises the bug and may be used to reproduce it. bashbug inserts the first three items automatically into the template it provides for filing a bug report.

Please send all reports concerning this manual to bug-bash@gnu.org.

Appendix B: Major Differences From The Bourne Shell

146

Appendix B Major Differences From The Bourne

Shell

Bash implements essentially the same grammar, parameter and variable expansion, redirec- tion, and quoting as the Bourne Shell. Bash uses the posix standard as the specification of how these features are to be implemented. There are some differences between the tradi- tional Bourne shell and Bash; this section quickly details the differences of significance. A number of these differences are explained in greater depth in previous sections. This section uses the version of sh included in SVR4.2 (the last version of the historical Bourne shell) as the baseline reference.

• Bash is posix-conformant, even where the posix specification differs from traditional sh behavior (see Section 6.11 [Bash POSIX Mode], page 94).

• Bash has multi-character invocation options (see Section 6.1 [Invoking Bash], page 80).

• Bash has command-line editing (see Chapter 8 [Command Line Editing], page 101) and the bind builtin.

• Bash provides a programmable word completion mechanism (see Section 8.6 [Pro- grammable Completion], page 124), and builtin commands complete, compgen, and compopt, to manipulate it.

• Bash has command history (see Section 9.1 [Bash History Facilities], page 133) and the history and fc builtins to manipulate it. The Bash history list maintains timestamp information and uses the value of the HISTTIMEFORMAT variable to display it.

• Bash implements csh-like history expansion (see Section 9.3 [History Interaction], page 135).

• Bash has one-dimensional array variables (see Section 6.7 [Arrays], page 89), and the appropriate variable expansions and assignment syntax to use them. Several of the

Bash builtins take options to act on arrays. Bash provides a number of built-in array variables.

• The $’...’ quoting syntax, which expands ANSI-C backslash-escaped characters in the text between the single quotes, is supported (see Section 3.1.2.4 [ANSI-C Quoting], page 6).

• Bash supports the $"..." quoting syntax to do locale-specific translation of the char- acters between the double quotes. The -D, --dump-strings, and --dump-po-strings invocation options list the translatable strings found in a script (see Section 3.1.2.5

[Locale Translation], page 7).

• Bash implements the ! keyword to negate the return value of a pipeline (see

Section 3.2.2 [Pipelines], page 8). Very useful when an if statement needs to act only if a test fails. The Bash ‘-o pipefail’ option to set will cause a pipeline to return a failure status if any command fails.

• Bash has the time reserved word and command timing (see Section 3.2.2 [Pipelines], page 8). The display of the timing statistics may be controlled with the TIMEFORMAT variable.

• Bash implements the for (( expr1 ; expr2 ; expr3 )) arithmetic for command, sim- ilar to the C language (see Section 3.2.4.1 [Looping Constructs], page 10).

• Bash includes the select compound command, which allows the generation of simple menus (see Section 3.2.4.2 [Conditional Constructs], page 10).

Appendix B: Major Differences From The Bourne Shell

147

• Bash includes the [[ compound command, which makes conditional testing part of the shell grammar (see Section 3.2.4.2 [Conditional Constructs], page 10), including optional regular expression matching.

• Bash provides optional case-insensitive matching for the case and [[ constructs.

• Bash includes brace expansion (see Section 3.5.1 [Brace Expansion], page 21) and tilde expansion (see Section 3.5.2 [Tilde Expansion], page 22).

• Bash implements command aliases and the alias and unalias builtins (see Section 6.6

[Aliases], page 88).

• Bash provides shell arithmetic, the (( compound command (see Section 3.2.4.2 [Con- ditional Constructs], page 10), and arithmetic expansion (see Section 6.5 [Shell Arith- metic], page 87).

• Variables present in the shell’s initial environment are automatically exported to child processes. The Bourne shell does not normally do this unless the variables are explicitly marked using the export command.

• Bash supports the ‘+=’ assignment operator, which appends to the value of the variable named on the left hand side.

• Bash includes the posix pattern removal ‘%’, ‘#’, ‘%%’ and ‘##’ expansions to remove leading or trailing substrings from variable values (see Section 3.5.3 [Shell Parameter

Expansion], page 23).

• The expansion ${#xx}, which returns the length of ${xx}, is supported (see

Section 3.5.3 [Shell Parameter Expansion], page 23).

• The expansion ${var:offset[:length]}, which expands to the substring of var’s value of length length, beginning at offset, is present (see Section 3.5.3 [Shell Parameter

Expansion], page 23).

• The expansion ${var/[/]pattern[/replacement]}, which matches pattern and replaces it with replacement in the value of var, is available (see Section 3.5.3 [Shell Parameter

Expansion], page 23).

• The expansion ${!prefix*} expansion, which expands to the names of all shell vari- ables whose names begin with prefix, is available (see Section 3.5.3 [Shell Parameter

Expansion], page 23).

• Bash has indirect variable expansion using ${!word} (see Section 3.5.3 [Shell Parameter

Expansion], page 23).

• Bash can expand positional parameters beyond $9 using ${num}.

• The posix $() form of command substitution is implemented (see Section 3.5.4 [Com- mand Substitution], page 28), and preferred to the Bourne shell’s ‘‘ (which is also implemented for backwards compatibility).

• Bash has process substitution (see Section 3.5.6 [Process Substitution], page 29).

• Bash automatically assigns variables that provide information about the current user (UID, EUID, and GROUPS), the current host (HOSTTYPE, OSTYPE, MACHTYPE, and

HOSTNAME), and the instance of Bash that is running (BASH, BASH_VERSION, and

BASH_VERSINFO). See Section 5.2 [Bash Variables], page 69, for details.

• The IFS variable is used to split only the results of expansion, not all words (see

Section 3.5.7 [Word Splitting], page 29). This closes a longstanding shell security hole.

Appendix B: Major Differences From The Bourne Shell

148

• The filename expansion bracket expression code uses ‘!’ and ‘^’ to negate the set of characters between the brackets. The Bourne shell uses only ‘!’.

• Bash implements the full set of posix filename expansion operators, including char- acter classes, equivalence classes, and collating symbols (see Section 3.5.8 [Filename

Expansion], page 30).

• Bash implements extended pattern matching features when the extglob shell option is enabled (see Section 3.5.8.1 [Pattern Matching], page 30).

• It is possible to have a variable and a function with the same name; sh does not separate the two name spaces.

• Bash functions are permitted to have local variables using the local builtin, and thus useful recursive functions may be written (see Section 4.2 [Bash Builtins], page 48).

• Variable assignments preceding commands affect only that command, even builtins and functions (see Section 3.7.4 [Environment], page 37). In sh, all variable assignments preceding commands are global unless the command is executed from the file system.

• Bash performs filename expansion on filenames specified as operands to input and output redirection operators (see Section 3.6 [Redirections], page 31).

• Bash contains the ‘<>’ redirection operator, allowing a file to be opened for both read- ing and writing, and the ‘&>’ redirection operator, for directing standard output and standard error to the same file (see Section 3.6 [Redirections], page 31).

• Bash includes the ‘<<<’ redirection operator, allowing a string to be used as the standard input to a command.

• Bash implements the ‘[n]<&word’ and ‘[n]>&word’ redirection operators, which move one file descriptor to another.

• Bash treats a number of filenames specially when they are used in redirection operators

(see Section 3.6 [Redirections], page 31).

• Bash can open network connections to arbitrary machines and services with the redi- rection operators (see Section 3.6 [Redirections], page 31).

• The noclobber option is available to avoid overwriting existing files with output redi- rection (see Section 4.3.1 [The Set Builtin], page 58). The ‘>|’ redirection operator may be used to override noclobber.

• The Bash cd and pwd builtins (see Section 4.1 [Bourne Shell Builtins], page 41) each take -L and -P options to switch between logical and physical modes.

• Bash allows a function to override a builtin with the same name, and provides access to that builtin’s functionality within the function via the builtin and command builtins

(see Section 4.2 [Bash Builtins], page 48).

• The command builtin allows selective disabling of functions when command lookup is performed (see Section 4.2 [Bash Builtins], page 48).

• Individual builtins may be enabled or disabled using the enable builtin (see Section 4.2

[Bash Builtins], page 48).

• The Bash exec builtin takes additional options that allow users to control the contents of the environment passed to the executed command, and what the zeroth argument to the command is to be (see Section 4.1 [Bourne Shell Builtins], page 41).

• Shell functions may be exported to children via the environment using export -f (see

Section 3.3 [Shell Functions], page 17).

Appendix B: Major Differences From The Bourne Shell

149

• The Bash export, readonly, and declare builtins can take a -f option to act on shell functions, a -p option to display variables with various attributes set in a format that can be used as shell input, a -n option to remove various variable attributes, and

‘name=value’ arguments to set variable attributes and values simultaneously.

• The Bash hash builtin allows a name to be associated with an arbitrary filename, even when that filename cannot be found by searching the $PATH, using ‘hash -p’ (see

Section 4.1 [Bourne Shell Builtins], page 41).

• Bash includes a help builtin for quick reference to shell facilities (see Section 4.2 [Bash

Builtins], page 48).

• The printf builtin is available to display formatted output (see Section 4.2 [Bash

Builtins], page 48).

• The Bash read builtin (see Section 4.2 [Bash Builtins], page 48) will read a line ending in ‘\’ with the -r option, and will use the REPLY variable as a default if no non-option arguments are supplied. The Bash read builtin also accepts a prompt string with the

-p option and will use Readline to obtain the line when given the -e option. The read builtin also has additional options to control input: the -s option will turn off echoing of input characters as they are read, the -t option will allow read to time out if input does not arrive within a specified number of seconds, the -n option will allow reading only a specified number of characters rather than a full line, and the -d option will read until a particular character rather than newline.

• The return builtin may be used to abort execution of scripts executed with the . or source builtins (see Section 4.1 [Bourne Shell Builtins], page 41).

• Bash includes the shopt builtin, for finer control of shell optional capabilities (see

Section 4.3.2 [The Shopt Builtin], page 62), and allows these options to be set and unset at shell invocation (see Section 6.1 [Invoking Bash], page 80).

• Bash has much more optional behavior controllable with the set builtin (see

Section 4.3.1 [The Set Builtin], page 58).

• The ‘-x’ (xtrace) option displays commands other than simple commands when per- forming an execution trace (see Section 4.3.1 [The Set Builtin], page 58).

• The test builtin (see Section 4.1 [Bourne Shell Builtins], page 41) is slightly different, as it implements the posix algorithm, which specifies the behavior based on the number of arguments.

• Bash includes the caller builtin, which displays the context of any active subroutine call (a shell function or a script executed with the . or source builtins). This supports the bash debugger.

• The trap builtin (see Section 4.1 [Bourne Shell Builtins], page 41) allows a DEBUG pseudo-signal specification, similar to EXIT. Commands specified with a DEBUG trap are executed before every simple command, for command, case command, select command, every arithmetic for command, and before the first command executes in a shell function. The DEBUG trap is not inherited by shell functions unless the function has been given the trace attribute or the functrace option has been enabled using the shopt builtin. The extdebug shell option has additional effects on the DEBUG trap.

The trap builtin (see Section 4.1 [Bourne Shell Builtins], page 41) allows an ERR pseudo- signal specification, similar to EXIT and DEBUG. Commands specified with an ERR trap

Appendix B: Major Differences From The Bourne Shell

150 are executed after a simple command fails, with a few exceptions. The ERR trap is not inherited by shell functions unless the -o errtrace option to the set builtin is enabled.

The trap builtin (see Section 4.1 [Bourne Shell Builtins], page 41) allows a RETURN pseudo-signal specification, similar to EXIT and DEBUG. Commands specified with an

RETURN trap are executed before execution resumes after a shell function or a shell script executed with . or source returns. The RETURN trap is not inherited by shell functions unless the function has been given the trace attribute or the functrace option has been enabled using the shopt builtin.

• The Bash type builtin is more extensive and gives more information about the names it finds (see Section 4.2 [Bash Builtins], page 48).

• The Bash umask builtin permits a -p option to cause the output to be displayed in the form of a umask command that may be reused as input (see Section 4.1 [Bourne Shell

Builtins], page 41).

• Bash implements a csh-like directory stack, and provides the pushd, popd, and dirs builtins to manipulate it (see Section 6.8 [The Directory Stack], page 90). Bash also makes the directory stack visible as the value of the DIRSTACK shell variable.

• Bash interprets special backslash-escaped characters in the prompt strings when inter- active (see Section 6.9 [Controlling the Prompt], page 92).

• The Bash restricted mode is more useful (see Section 6.10 [The Restricted Shell], page 93); the SVR4.2 shell restricted mode is too limited.

• The disown builtin can remove a job from the internal shell job table (see Section 7.2

[Job Control Builtins], page 98) or suppress the sending of SIGHUP to a job when the shell exits as the result of a SIGHUP.

• Bash includes a number of features to support a separate debugger for shell scripts.

• The SVR4.2 shell has two privilege-related builtins (mldmode and priv) not present in

Bash.

• Bash does not have the stop or newgrp builtins.

• Bash does not use the SHACCT variable or perform shell accounting.

• The SVR4.2 sh uses a TIMEOUT variable like Bash uses TMOUT.

More features unique to Bash may be found in Chapter 6 [Bash Features], page 80.

B.1 Implementation Differences From The SVR4.2 Shell

Since Bash is a completely new implementation, it does not suffer from many of the limi- tations of the SVR4.2 shell. For instance:

• Bash does not fork a subshell when redirecting into or out of a shell control structure such as an if or while statement.

• Bash does not allow unbalanced quotes. The SVR4.2 shell will silently insert a needed closing quote at EOF under certain circumstances. This can be the cause of some hard- to-find errors.

• The SVR4.2 shell uses a baroque memory management scheme based on trapping

SIGSEGV. If the shell is started from a process with SIGSEGV blocked (e.g., by using the system() C library function call), it misbehaves badly.

Appendix B: Major Differences From The Bourne Shell

151

• In a questionable attempt at security, the SVR4.2 shell, when invoked without the -p option, will alter its real and effective uid and gid if they are less than some magic threshold value, commonly 100. This can lead to unexpected results.

• The SVR4.2 shell does not allow users to trap SIGSEGV, SIGALRM, or SIGCHLD.

• The SVR4.2 shell does not allow the IFS, MAILCHECK, PATH, PS1, or PS2 variables to be unset.

• The SVR4.2 shell treats ‘^’ as the undocumented equivalent of ‘|’.

• Bash allows multiple option arguments when it is invoked (-x -v); the SVR4.2 shell allows only one option argument (-xv). In fact, some versions of the shell dump core if the second argument begins with a ‘-’.

• The SVR4.2 shell exits a script if any builtin fails; Bash exits a script only if one of the posix special builtins fails, and only for certain failures, as enumerated in the posix standard.

• The SVR4.2 shell behaves differently when invoked as jsh (it turns on job control).

Appendix C: GNU Free Documentation License

152

Appendix C GNU Free Documentation License

Version 1.3, 3 November 2008

Copyright c

2000, 2001, 2002, 2007, 2008 Free Software Foundation, Inc. http://fsf.org/

Everyone is permitted to copy and distribute verbatim copies of this license document, but changing it is not allowed.

0. PREAMBLE

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Sections with the same name but different contents, make the title of each such section unique by adding at the end of it, in parentheses, the name of the original author or publisher of that section if known, or else a unique number. Make the same adjustment to the section titles in the list of Invariant Sections in the license notice of the combined work.

In the combination, you must combine any sections Entitled “History” in the vari- ous original documents, forming one section Entitled “History”; likewise combine any sections Entitled “Acknowledgements”, and any sections Entitled “Dedications”. You must delete all sections Entitled “Endorsements.”

6. COLLECTIONS OF DOCUMENTS

You may make a collection consisting of the Document and other documents released under this License, and replace the individual copies of this License in the various documents with a single copy that is included in the collection, provided that you follow the rules of this License for verbatim copying of each of the documents in all other respects.

You may extract a single document from such a collection, and distribute it individu- ally under this License, provided you insert a copy of this License into the extracted document, and follow this License in all other respects regarding verbatim copying of that document.

Appendix C: GNU Free Documentation License

157

7. AGGREGATION WITH INDEPENDENT WORKS

A compilation of the Document or its derivatives with other separate and independent documents or works, in or on a volume of a storage or distribution medium, is called an “aggregate” if the copyright resulting from the compilation is not used to limit the legal rights of the compilation’s users beyond what the individual works permit. When the Document is included in an aggregate, this License does not apply to the other works in the aggregate which are not themselves derivative works of the Document.

If the Cover Text requirement of section 3 is applicable to these copies of the Document, then if the Document is less than one half of the entire aggregate, the Document’s Cover

Texts may be placed on covers that bracket the Document within the aggregate, or the electronic equivalent of covers if the Document is in electronic form. Otherwise they must appear on printed covers that bracket the whole aggregate.

8. TRANSLATION

Translation is considered a kind of modification, so you may distribute translations of the Document under the terms of section 4.

Replacing Invariant Sections with translations requires special permission from their copyright holders, but you may include translations of some or all Invariant Sections in addition to the original versions of these Invariant Sections. You may include a translation of this License, and all the license notices in the Document, and any Warranty Disclaimers, provided that you also include the original English version of this License and the original versions of those notices and disclaimers. In case of a disagreement between the translation and the original version of this License or a notice or disclaimer, the original version will prevail.

If a section in the Document is Entitled “Acknowledgements”, “Dedications”, or “His- tory”, the requirement (section 4) to Preserve its Title (section 1) will typically require changing the actual title.

9. TERMINATION

You may not copy, modify, sublicense, or distribute the Document except as expressly provided under this License. Any attempt otherwise to copy, modify, sublicense, or distribute it is void, and will automatically terminate your rights under this License.

However, if you cease all violation of this License, then your license from a particular copyright holder is reinstated (a) provisionally, unless and until the copyright holder explicitly and finally terminates your license, and (b) permanently, if the copyright holder fails to notify you of the violation by some reasonable means prior to 60 days after the cessation.

Moreover, your license from a particular copyright holder is reinstated permanently if the copyright holder notifies you of the violation by some reasonable means, this is the first time you have received notice of violation of this License (for any work) from that copyright holder, and you cure the violation prior to 30 days after your receipt of the notice.

Termination of your rights under this section does not terminate the licenses of parties who have received copies or rights from you under this License. If your rights have been terminated and not permanently reinstated, receipt of a copy of some or all of the same material does not give you any rights to use it.

Appendix C: GNU Free Documentation License

158

10. FUTURE REVISIONS OF THIS LICENSE

The Free Software Foundation may publish new, revised versions of the GNU Free

Documentation License from time to time. Such new versions will be similar in spirit to the present version, but may differ in detail to address new problems or concerns.

See http://www.gnu.org/copyleft/.

Each version of the License is given a distinguishing version number. If the Document specifies that a particular numbered version of this License “or any later version” applies to it, you have the option of following the terms and conditions either of that specified version or of any later version that has been published (not as a draft) by the Free Software Foundation. If the Document does not specify a version number of this License, you may choose any version ever published (not as a draft) by the Free

Software Foundation. If the Document specifies that a proxy can decide which future versions of this License can be used, that proxy’s public statement of acceptance of a version permanently authorizes you to choose that version for the Document.

11. RELICENSING

“Massive Multiauthor Collaboration Site” (or “MMC Site”) means any World Wide

Web server that publishes copyrightable works and also provides prominent facilities for anybody to edit those works. A public wiki that anybody can edit is an example of such a server. A “Massive Multiauthor Collaboration” (or “MMC”) contained in the site means any set of copyrightable works thus published on the MMC site.

“CC-BY-SA” means the Creative Commons Attribution-Share Alike 3.0 license pub- lished by Creative Commons Corporation, a not-for-profit corporation with a principal place of business in San Francisco, California, as well as future copyleft versions of that license published by that same organization.

“Incorporate” means to publish or republish a Document, in whole or in part, as part of another Document.

An MMC is “eligible for relicensing” if it is licensed under this License, and if all works that were first published under this License somewhere other than this MMC, and subsequently incorporated in whole or in part into the MMC, (1) had no cover texts or invariant sections, and (2) were thus incorporated prior to November 1, 2008.

The operator of an MMC Site may republish an MMC contained in the site under

CC-BY-SA on the same site at any time before August 1, 2009, provided the MMC is eligible for relicensing.

Appendix C: GNU Free Documentation License

159

ADDENDUM: How to use this License for your documents

To use this License in a document you have written, include a copy of the License in the document and put the following copyright and license notices just after the title page:

Copyright (C) year your name.

Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.3 or any later version published by the Free Software Foundation; with no Invariant Sections, no Front-Cover Texts, and no Back-Cover

Texts.

A copy of the license is included in the section entitled ‘‘GNU

Free Documentation License’’.

If you have Invariant Sections, Front-Cover Texts and Back-Cover Texts, replace the

“with. . . Texts.” line with this: with the Invariant Sections being list their titles, with the Front-Cover Texts being list, and with the Back-Cover Texts being list.

If you have Invariant Sections without Cover Texts, or some other combination of the three, merge those two alternatives to suit the situation.

If your document contains nontrivial examples of program code, we recommend releasing these examples in parallel under your choice of free software license, such as the GNU

General Public License, to permit their use in free software.

Appendix D: Indexes

160

Appendix D Indexes

D.1 Index of Shell Builtin Commands

.

G

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 getopts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43

:

H

: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 hash . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44 help . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

[ history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 134

[ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45

J

A jobs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98 alias . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48

K

B kill . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99 bg . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98 bind . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48

L break . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 builtin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49 let . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53 local . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

C logout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53 caller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50 cd . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42

M command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50 mapfile . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54 compgen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 126 complete . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127 compopt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 130

P continue . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42 popd . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91

D printf . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54 pushd . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91 declare . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50 pwd . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44 dirs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90 disown . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99

R

E read . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55 readarray . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56 echo . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52 readonly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44 enable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52 return . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 eval . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42 exec . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43 exit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43

S export . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43 set . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58 shift . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45

F shopt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62 source . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56 fc . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133 suspend . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99 fg . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98

Appendix D: Indexes

161

T

U test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 ulimit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57 times . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46 umask . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47 trap . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47 unalias . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58 unset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48 type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56 typeset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57

W wait . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99

D.2 Index of Shell Reserved Words

! esac . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

! . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

F

[ fi . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

[[ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 for . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

]

I

]] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 if . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 in . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

|

{ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

S

} . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 select . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

C

T case . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 then . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

D do . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

U done . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 until . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

E

W elif . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 else . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 while . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

D.3 Parameter and Variable Index

!

$! . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

! . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

$# . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

$$ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

$* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

#

$- . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

# . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

$? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

$@ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

$_ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

$

$0 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

$ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

Appendix D: Indexes

162

*

COMP_KEY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73

* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

COMP_LINE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72

COMP_POINT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72

COMP_TYPE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73

-

COMP_WORDBREAKS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73

- . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

COMP_WORDS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73 completion-display-width . . . . . . . . . . . . . . . . . . 105 completion-ignore-case . . . . . . . . . . . . . . . . . . . . . 105

? completion-map-case . . . . . . . . . . . . . . . . . . . . . . . . 105

? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 completion-prefix-display-length . . . . . . . . . 106 completion-query-items . . . . . . . . . . . . . . . . . . . . . 106

COMPREPLY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73

@ convert-meta . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106

@ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

COPROC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73

D

_ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

DIRSTACK . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73 disable-completion . . . . . . . . . . . . . . . . . . . . . . . . . 106

0

E

0 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 editing-mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106

A

EMACS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73 enable-keypad . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106 auto_resume . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100

ENV . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73

EUID . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73 expand-tilde . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106

B

BASH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69

F

BASH_ALIASES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70

BASH_ARGC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70

FCEDIT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73

BASH_ARGV . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70

FIGNORE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74

BASH_CMDS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70

FUNCNAME . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74

BASH_COMMAND . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70

FUNCNEST . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74

BASH_COMPAT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70

BASH_ENV . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71

G

BASH_EXECUTION_STRING . . . . . . . . . . . . . . . . . . . . . . . 71

BASH_LINENO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71

GLOBIGNORE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74

BASH_REMATCH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71

GROUPS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74

BASH_SOURCE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71

BASH_SUBSHELL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71

H

BASH_VERSINFO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71

BASH_VERSION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72 histchars . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74

BASH_XTRACEFD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72

HISTCMD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74

BASHOPTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70

HISTCONTROL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74

BASHPID . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70

HISTFILE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75 bell-style . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105

HISTFILESIZE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75 bind-tty-special-chars . . . . . . . . . . . . . . . . . . . . . 105

HISTIGNORE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75 history-preserve-point . . . . . . . . . . . . . . . . . . . . . 107 history-size . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107

C

HISTSIZE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75

CDPATH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69

HISTTIMEFORMAT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75

CHILD_MAX . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72

HOME . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69 colored-stats . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105 horizontal-scroll-mode . . . . . . . . . . . . . . . . . . . . . 107

COLUMNS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72

HOSTFILE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75 comment-begin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105

HOSTNAME . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76

COMP_CWORD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72

HOSTTYPE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76

Appendix D: Indexes

163

I

PATH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69

IFS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69

PIPESTATUS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77

IGNOREEOF . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76

POSIXLY_CORRECT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77 input-meta . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107

PPID . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77

INPUTRC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76

PROMPT_COMMAND . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77 isearch-terminators . . . . . . . . . . . . . . . . . . . . . . . . 107

PROMPT_DIRTRIM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77

PS1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69

PS2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69

K

PS3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77 keymap . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107

PS4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77

PWD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77

L

R

LANG . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76

LC_ALL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76

RANDOM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77

LC_COLLATE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76

READLINE_LINE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78

LC_CTYPE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76

READLINE_POINT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78

LC_MESSAGES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7, 76

REPLY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78

LC_NUMERIC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76 revert-all-at-newline . . . . . . . . . . . . . . . . . . . . . . 108

LINENO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76

LINES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76

S

M

SECONDS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78

SHELL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78

MACHTYPE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76

SHELLOPTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78

MAIL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69

SHLVL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78

MAILCHECK . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77 show-all-if-ambiguous . . . . . . . . . . . . . . . . . . . . . . 109

MAILPATH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69 show-all-if-unmodified . . . . . . . . . . . . . . . . . . . . . 109

MAPFILE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77 show-mode-in-prompt . . . . . . . . . . . . . . . . . . . . . . . . 109 mark-modified-lines . . . . . . . . . . . . . . . . . . . . . . . . 108 skip-completed-text . . . . . . . . . . . . . . . . . . . . . . . . 109 mark-symlinked-directories . . . . . . . . . . . . . . . . 108 match-hidden-files . . . . . . . . . . . . . . . . . . . . . . . . . 108 menu-complete-display-prefix . . . . . . . . . . . . . . 108

T meta-flag . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107

TEXTDOMAIN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

TEXTDOMAINDIR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

O

TIMEFORMAT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78

OLDPWD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77

TMOUT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79

OPTARG . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69

TMPDIR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79

OPTERR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77

OPTIND . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69

U

OSTYPE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77 output-meta . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108

UID . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79

P

V page-completions . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108 visible-stats . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 109

D.4 Function Index

A

B abort (C-g) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122 backward-char (C-b) . . . . . . . . . . . . . . . . . . . . . . . . 115 accept-line (Newline or Return) . . . . . . . . . . . 116 backward-delete-char (Rubout) . . . . . . . . . . . . . 117 alias-expand-line () . . . . . . . . . . . . . . . . . . . . . . . 124 backward-kill-line (C-x Rubout) . . . . . . . . . . . 118 backward-kill-word (M-DEL) . . . . . . . . . . . . . . . . 119

Appendix D: Indexes

164 backward-word (M-b) . . . . . . . . . . . . . . . . . . . . . . . . 115 glob-expand-word (C-x *) . . . . . . . . . . . . . . . . . . . 123 beginning-of-history (M-<) . . . . . . . . . . . . . . . . 116 glob-list-expansions (C-x g) . . . . . . . . . . . . . . . 123 beginning-of-line (C-a) . . . . . . . . . . . . . . . . . . . . 115

H

C history-and-alias-expand-line () . . . . . . . . . . 124 call-last-kbd-macro (C-x e) . . . . . . . . . . . . . . . . 121 history-expand-line (M-^) . . . . . . . . . . . . . . . . . . 123 capitalize-word (M-c) . . . . . . . . . . . . . . . . . . . . . . 118 history-search-backward () . . . . . . . . . . . . . . . . 116 character-search (C-]) . . . . . . . . . . . . . . . . . . . . . 122 history-search-forward () . . . . . . . . . . . . . . . . . . 116 character-search-backward (M-C-]) . . . . . . . . 122 history-substr-search-backward () . . . . . . . . 117 clear-screen (C-l) . . . . . . . . . . . . . . . . . . . . . . . . . . 115 history-substr-search-forward () . . . . . . . . . . 116 complete (TAB) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120 complete-command (M-!) . . . . . . . . . . . . . . . . . . . . . 121 complete-filename (M-/) . . . . . . . . . . . . . . . . . . . . 120

I complete-hostname (M-@) . . . . . . . . . . . . . . . . . . . . 121 insert-comment (M-#) . . . . . . . . . . . . . . . . . . . . . . . 123 complete-into-braces (M-{) . . . . . . . . . . . . . . . . 121 insert-completions (M-*) . . . . . . . . . . . . . . . . . . . 120 complete-username (M-~) . . . . . . . . . . . . . . . . . . . . 121 insert-last-argument (M-. or M-_) . . . . . . . . . 124 complete-variable (M-$) . . . . . . . . . . . . . . . . . . . . 121 copy-backward-word () . . . . . . . . . . . . . . . . . . . . . . 119 copy-forward-word () . . . . . . . . . . . . . . . . . . . . . . . 119

K copy-region-as-kill () . . . . . . . . . . . . . . . . . . . . . 119 kill-line (C-k) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118 kill-region () . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119

D kill-whole-line () . . . . . . . . . . . . . . . . . . . . . . . . . . 118 kill-word (M-d) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118 dabbrev-expand () . . . . . . . . . . . . . . . . . . . . . . . . . . . 121 delete-char (C-d) . . . . . . . . . . . . . . . . . . . . . . . . . . . 117 delete-char-or-list () . . . . . . . . . . . . . . . . . . . . . 120

M delete-horizontal-space () . . . . . . . . . . . . . . . . 119 digit-argument (M-0, M-1, ... M--) . . . . . . . . 119 magic-space () . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 124 display-shell-version (C-x C-v) . . . . . . . . . . . 123 menu-complete () . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120 do-uppercase-version (M-a, M-b, M-x, ...) menu-complete-backward () . . . . . . . . . . . . . . . . . . 120

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122 downcase-word (M-l) . . . . . . . . . . . . . . . . . . . . . . . . 118 dump-functions () . . . . . . . . . . . . . . . . . . . . . . . . . . . 123

N dump-macros () . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123 next-history (C-n) . . . . . . . . . . . . . . . . . . . . . . . . . . 116 dump-variables () . . . . . . . . . . . . . . . . . . . . . . . . . . . 123 non-incremental-forward-search-history (M-n) dynamic-complete-history (M-TAB) . . . . . . . . . . 121

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116 non-incremental-reverse-search-history (M-p)

E

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116 edit-and-execute-command (C-xC-e) . . . . . . . . 124

O end-kbd-macro (C-x )) . . . . . . . . . . . . . . . . . . . . . . . 121 end-of-file (usually C-d) . . . . . . . . . . . . . . . . . . 117 operate-and-get-next (C-o) . . . . . . . . . . . . . . . . 124 end-of-history (M->) . . . . . . . . . . . . . . . . . . . . . . . 116 overwrite-mode () . . . . . . . . . . . . . . . . . . . . . . . . . . . 118 end-of-line (C-e) . . . . . . . . . . . . . . . . . . . . . . . . . . . 115 exchange-point-and-mark (C-x C-x) . . . . . . . . . 122

P

F possible-command-completions (C-x !) . . . . . 121 possible-completions (M-?) . . . . . . . . . . . . . . . . 120 forward-backward-delete-char () . . . . . . . . . . . 117 possible-filename-completions (C-x /) . . . . 120 forward-char (C-f) . . . . . . . . . . . . . . . . . . . . . . . . . . 115 possible-hostname-completions (C-x @) . . . . 121 forward-search-history (C-s) . . . . . . . . . . . . . . 116 possible-username-completions (C-x ~) . . . . 121 forward-word (M-f) . . . . . . . . . . . . . . . . . . . . . . . . . . 115 possible-variable-completions (C-x $) . . . . 121 prefix-meta (ESC) . . . . . . . . . . . . . . . . . . . . . . . . . . . 122

G previous-history (C-p) . . . . . . . . . . . . . . . . . . . . . 116 print-last-kbd-macro () . . . . . . . . . . . . . . . . . . . . 122 glob-complete-word (M-g) . . . . . . . . . . . . . . . . . . . 123

Appendix D: Indexes

165

Q

T quoted-insert (C-q or C-v) . . . . . . . . . . . . . . . . . 117 tilde-expand (M-&) . . . . . . . . . . . . . . . . . . . . . . . . . . 122 transpose-chars (C-t) . . . . . . . . . . . . . . . . . . . . . . 118

R transpose-words (M-t) . . . . . . . . . . . . . . . . . . . . . . 118 re-read-init-file (C-x C-r) . . . . . . . . . . . . . . . . 122 redraw-current-line () . . . . . . . . . . . . . . . . . . . . . 115

U reverse-search-history (C-r) . . . . . . . . . . . . . . 116 undo (C-_ or C-x C-u) . . . . . . . . . . . . . . . . . . . . . . . 122 revert-line (M-r) . . . . . . . . . . . . . . . . . . . . . . . . . . . 122 universal-argument () . . . . . . . . . . . . . . . . . . . . . . 119 unix-filename-rubout () . . . . . . . . . . . . . . . . . . . . 119

S unix-line-discard (C-u) . . . . . . . . . . . . . . . . . . . . 118 unix-word-rubout (C-w) . . . . . . . . . . . . . . . . . . . . . 119 self-insert (a, b, A, 1, !, ...) . . . . . . . . . . . . 118 upcase-word (M-u) . . . . . . . . . . . . . . . . . . . . . . . . . . . 118 set-mark (C-@) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122 shell-backward-kill-word () . . . . . . . . . . . . . . . 119 shell-backward-word () . . . . . . . . . . . . . . . . . . . . . 115

Y shell-expand-line (M-C-e) . . . . . . . . . . . . . . . . . . 123 shell-forward-word () . . . . . . . . . . . . . . . . . . . . . . 115 yank (C-y) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119 shell-kill-word () . . . . . . . . . . . . . . . . . . . . . . . . . . 119 yank-last-arg (M-. or M-_) . . . . . . . . . . . . . . . . . 117 skip-csi-sequence () . . . . . . . . . . . . . . . . . . . . . . . 122 yank-nth-arg (M-C-y) . . . . . . . . . . . . . . . . . . . . . . . 117 start-kbd-macro (C-x () . . . . . . . . . . . . . . . . . . . . 121 yank-pop (M-y) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119

D.5 Concept Index

A commands, shell . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 alias expansion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88 commands, simple . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 arithmetic evaluation . . . . . . . . . . . . . . . . . . . . . . . . . . 87 comments, shell . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 arithmetic expansion . . . . . . . . . . . . . . . . . . . . . . . . . . 29 completion builtins . . . . . . . . . . . . . . . . . . . . . . . . . . . 126 arithmetic, shell . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87 configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 138 arrays . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89 control operator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 coprocess . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

B

D background . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97

Bash configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . 138 directory stack . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90

Bash installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 138

Bourne shell . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 brace expansion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

E builtin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 editing command lines . . . . . . . . . . . . . . . . . . . . . . . . 102 environment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

C evaluation, arithmetic . . . . . . . . . . . . . . . . . . . . . . . . . 87 event designators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135 command editing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102 execution environment . . . . . . . . . . . . . . . . . . . . . . . . . 36 command execution . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 exit status . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3, 38 command expansion . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 expansion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 command history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133 expansion, arithmetic . . . . . . . . . . . . . . . . . . . . . . . . . . 29 command search . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 expansion, brace . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 command substitution . . . . . . . . . . . . . . . . . . . . . . . . . 28 expansion, filename . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 command timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 expansion, parameter . . . . . . . . . . . . . . . . . . . . . . . . . . 23 commands, compound . . . . . . . . . . . . . . . . . . . . . . . . . . 9 expansion, pathname . . . . . . . . . . . . . . . . . . . . . . . . . . 30 commands, conditional . . . . . . . . . . . . . . . . . . . . . . . . 10 commands, grouping . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 expansion, tilde . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 commands, lists. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 expressions, arithmetic . . . . . . . . . . . . . . . . . . . . . . . . . 87 commands, looping . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 expressions, conditional . . . . . . . . . . . . . . . . . . . . . . . . 85 commands, pipelines . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Appendix D: Indexes

166

F parameters, positional . . . . . . . . . . . . . . . . . . . . . . . . . 19 field . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 parameters, special . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 filename . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 pathname expansion . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 filename expansion . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 pattern matching . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 foreground . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97 pipeline . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 functions, shell . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

POSIX . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

POSIX Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94 process group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

H process group ID . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 process substitution . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 history builtins . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133 programmable completion . . . . . . . . . . . . . . . . . . . . 124 history events . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135 prompting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92 history expansion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135 history list . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133

History, how to use . . . . . . . . . . . . . . . . . . . . . . . . . . . 132

Q quoting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

I quoting, ANSI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 identifier . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 initialization file, readline . . . . . . . . . . . . . . . . . . . . . 104

R installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 138 interaction, readline . . . . . . . . . . . . . . . . . . . . . . . . . . 101

Readline, how to use . . . . . . . . . . . . . . . . . . . . . . . . . 100 interactive shell . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81, 83 redirection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 internationalization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 reserved word . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 restricted shell . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93 return status . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

J job . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

S job control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3, 97 shell arithmetic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87 shell function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

K shell script . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39 kill ring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103 shell variable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 killing text . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103 shell, interactive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83 signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 signal handling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

L special builtin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4, 68 startup files . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82 localization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 suspending jobs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97 login shell . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81

M

T matching, pattern . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 tilde expansion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 metacharacter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 token . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 translation, native languages . . . . . . . . . . . . . . . . . . . . 7

N

V name . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 native languages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 variable, shell . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 notation, readline . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102 variables, readline . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105

O

W operator, shell . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 word . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 word splitting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

P

Y parameter expansion . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 yanking text . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103