Editing Bash (Unix shell) (section)

{{Short description|GNU replacement for the Bourne shell}}
{{Use dmy dates|date=March 2014}}
{{ Infobox software
 | author = [[Brian Fox (programmer)|Brian Fox]]
 | caption = 
 | developer = Chet Ramey
 | genre = [[Shell (computing)]], [[Unix shell]], [[command language]]
 | language = Multilingual ([[gettext]])
 | latest release date =
  {{ wikidata
   | qualifier
   | preferred
   | single
   | Q189248
   | P348
   | P548 = Q2804309
   | P577
  }}
 | latest release version =
  {{ wikidata
   | property 
   | preferred 
   | references 
   | edit 
   | Q189248 
   | P348 
   | P548 = Q2804309
  }}
 | license = 
  {{ plainlist
   |
*   v.4.0+: [[GNU General Public License#Version 3|GPL-3.0-or-later]]<ref name="license">{{Cite web |last=GNU Project      |author-link=GNU Project      |title=README file      |url=https://www.gnu.org/software/bash/      |url-status=live     |archive-url=https://web.archive.org/web/20190426210620/http://www.gnu.org/software/bash/      |archive-date=26 April 2019      |access-date=16 April 2014      |quote=Bash is free software, distributed under the terms of the [GNU] General Public License as published by the Free Software Foundation, version 3 of the License (or any later version).     }}</ref>
*   v.1.11 – v.3.2: [[GNU General Public License#Version 2|GPL-2.0-or-later]]<ref>{{Cite web |title=bash-1.11      |url=http://www.oldlinux.org/Linux.old/bin/old/bash-1.11/      |url-status=dead      |archive-url=https://web.archive.org/web/20211015233550/http://www.oldlinux.org/Linux.old/bin/old/bash-1.11/      |archive-date=15 October 2021      |access-date=9 June 2021      |website=oldlinux.org     |quote=See test.c for GPL-2.0-or-later     }}</ref>
*   v.0.99 – v.1.05: [[GNU General Public License#Version 1|GPL-1.0-or-later]]<ref name="bashfaq061">{{Cite web |title=BashFAQ/061 |website=Greg's Wiki      |url=https://mywiki.wooledge.org/BashFAQ/061      |url-status=live      |archive-url=https://web.archive.org/web/20210302212811/https://mywiki.wooledge.org/BashFAQ/061      |archive-date=March 2, 2021      |access-date=2021-03-01      }}</ref><ref>{{ multiref2
     |
      {{Cite web |title=bash-1.05.tar        |url=http://www.oldlinux.org/Linux.old/bin/old/bash-1.05.tar        |website=oldlinux.org      }}
     |
      {{ cite web
       | title = Is there a way to download the presumably initial bash source bash-0.99?
       | url = https://unix.stackexchange.com/questions/243375/is-there-a-way-to-download-the-presumably-initial-bash-source-bash-0-99
       | website = unix.stackexchange.com
      }}
    }}</ref>
  }}
 | logo = Gnu-bash-logo.svg
 | name = Bash
 | operating system =
  {{ Plainlist 
   |
*   [[Linux]]
*   [[Unix-like]]
*   [[macOS]]
*   [[Windows]]
*   [[Android (operating system)|Android]]
*   [[Oracle Solaris]]
<!--*   [[Haiku (operating system)|Haiku]]-->
  }}
 | platform = [[GNU]]
 | programming language = [[C (programming language)|C]]
 | released = {{start date and age| 8 June 1989 }}
 | screenshot = 
 | website = {{URL|www.gnu.org/software/bash/}}
}}
In [[Computer science|computing]], '''Bash''' (short for "''Bourne Again SHell''",)<ref>{{ multiref2
 |
  {{Cite web |last=[[Richard Stallman]]    |date=November 12, 2010    |title=About the GNU Project    |url=https://www.gnu.org/gnu/thegnuproject.html    |url-status=live   |archive-url=https://web.archive.org/web/20110424064815/https://www.gnu.org/gnu/thegnuproject.html    |archive-date=24 April 2011    |access-date=13 March 2011    |publisher=Free Software Foundation    |quote="Bourne Again Shell" is a play on the name ''Bourne Shell'', which was the usual shell on Unix.   }}
 |
  {{ cite web
   | access-date = 13 March 2011
   | archive-date = 9 March 2011
   | archive-url = https://web.archive.org/web/20110309092607/http://www.markus-gattol.name/ws/bash.html
   | date = 13 March 2011
   | df = dmy-all
   | first = Markus
   | last = Gattol
   | quote = The name is a pun on the name of the Bourne shell (sh), an early and important Unix shell written by Stephen Bourne and distributed with Version 7 Unix circa 1978, and the concept of being 'born again'.
   | title = Bourne-again Shell
   | url = http://www.markus-gattol.name/ws/bash.html
   | url-status = dead
  }}
}}</ref> is an [[Human–computer interaction|interactive]] command interpreter and command programming language developed for [[UNIX]]-like operating systems.<ref>{{Cite web |title=Bourne shell  |url=https://www.ibm.com/docs/en/aix/latest?topic=shells-bourne-shell  |access-date=19 May 2024  |publisher=IBM |quote=The Bourne shell is an interactive command interpreter and command programming language. }}</ref> Created in 1989<ref name="BashBeta">{{Cite newsgroup |url=https://groups.google.com/group/gnu.announce/msg/a509f48ffb298c35?hl=en  |title=Bash is in beta release!  |last=Brian Fox (forwarded by Leonard H. Tower Jr.)  |date=8 June 1989  |newsgroup=gnu.announce  |archive-url=https://web.archive.org/web/20130504075535/http://groups.google.com/group/gnu.announce/msg/a509f48ffb298c35?hl=en  |archive-date=4 May 2013  |url-status=live |access-date=28 October 2010 }}</ref> by Brian Fox for the [[GNU Project]], it is supported by the [[Free Software Foundation]] and designed as a 100%  [[free software|free]] alternative for the [[Bourne shell]] (<code>sh</code>) and other proprietary Unix shells.<ref>{{ multiref2
 |
  {{Cite web |title=GNU in a Nutshell    |url=https://www.gnu.org/gnu/about-gnu.html    |access-date=19 May 2024    |publisher=[[GNU Project]]   |quote=The ultimate goal is to provide free software to do all of the jobs computer users want to do—and thus make proprietary software a thing of the past.   }}
 |
  {{ cite web
   | access-date = 19 May 2024
   | quote = The Free Software Foundation (FSF) is a nonprofit with a worldwide mission to promote computer user freedom.
   | title = Free Software Foundation — working together for free software — Front Page
   | url = https://www.fsf.org/
   | website = fsf.org
  }}
 |
  {{ cite web
   | access-date = 19 May 2024
   | quote = GNU is an operating system which is 100% free software.
   | title = GNU Software
   | url = https://www.gnu.org/software/software.en.html
   | website = gnu.org
  }}
 |
  {{ cite web
   | access-date = 19 May 2024
   | quote = Brian Fox has now completed GNU's version of sh, called BASH, the `Bourne Again SHell'.
   | title = GNU's Bulletin, vol. 1 no. 7, June, 1989 :: GNU's Who
   | url = https://www.gnu.org/bulletins/bull7.html#SEC3
   | website = gnu.org
  }}
}}</ref>

Since its inception, Bash has gained widespread adoption and is commonly used as the default [[login]] shell for numerous [[Linux]] distributions.<ref>{{ multiref2
 |
  {{cite journal
   | access-date = 21 March 2011
   | archive-date = 6 July 2011
   | archive-url = https://web.archive.org/web/20110706103704/http://www.computerworld.com.au/article/222764/a-z_programming_languages_bash_bourne-again_shell/?pp=2&fp=16&fpid=1
   | date = 30 May 2008
   | first = Naomi
   | journal = Computerworld
   | last = Hamilton
   | page = 2
   | quote = When Richard Stallman decided to create a full replacement for the then-encumbered Unix systems, he knew that he would eventually have to have replacements for all of the common utilities, especially the standard shell, and those replacements would have to have acceptable licensing.
   | title = The A-Z of Programming Languages: BASH/Bourne-Again Shell
   | url = http://www.computerworld.com.au/article/222764/a-z_programming_languages_bash_bourne-again_shell/?pp=2&fp=16&fpid=1
   | url-status = dead
   }}
 |
  {{cite web | title=The A-Z of Programming Languages: BASH/Bourne-Again Shell | website=A-Z 0.01 documentation | date=2008-05-30 | url=https://a-z.readthedocs.io/en/latest/bash.html }}
 |
  {{cite web |publisher= University of South Carolina |title=The A-Z of Programming Languages | url = https://cse.sc.edu/~mgv/csce330f16/pres/az.pdf }}
}}</ref><ref name="cmpwrld_intrw2008">{{Cite web|last=Hamilton     |first=Naomi     |date=30 March 2008    |title=The A-Z of Programming Languages: BASH/Bourne-Again Shell     | url=http://www.computerworld.com.au/article/222764/ | archive-url=https://web.archive.org/web/20160811002459/http://www.computerworld.com.au/article/222764/ | archive-date=2016-08-11 | url-status=dead |website=[[Computerworld]]}}</ref><ref name="goftw2015">{{Cite web |date=14 December 2015 |title=Chet Ramey: Geek of the Week |url=https://www.red-gate.com/simple-talk/opinion/geek-of-the-week/chet-ramey-geek-of-the-week/ |url-status=live |archive-url=https://web.archive.org/web/20200731032216/https://www.red-gate.com/simple-talk/opinion/geek-of-the-week/chet-ramey-geek-of-the-week/ |archive-date=31 Jul 2020 |access-date=April 26, 2025}}</ref> It holds historical significance as one of the earliest programs ported to Linux by [[Linus Torvalds]], alongside the GNU Compiler ([[GNU Compiler Collection|GCC]]).<ref>{{Cite newsgroup|last=Torvalds   |first=Linus Benedict   |date=August 1991  |title=What would you like to see most in minix? |newsgroup=comp.os.minix   |url=https://groups.google.com/group/comp.os.minix/msg/b813d52cbc5a044b  |access-date=2009-09-06   |quote=I've currently ported bash(1.08) and gcc(1.40), and things seem to work.  }}</ref> It is available on nearly all modern operating systems, making it a versatile tool in various computing environments.

As a [[command-line interface]] (CLI), Bash operates within a terminal emulator, or [[terminal emulator|text window]], where users input commands to execute various tasks. It also supports the execution of commands from files, known as [[shell script]]s, facilitating [[automation]]. In keeping with Unix shell conventions, Bash incorporates a rich set of features. The [[keyword (computer programming)|keywords]], [[syntax (programming languages)|syntax]], [[scope (computer science)#Dynamic scoping|dynamically scoped]] variables, and other basic features of the [[formal language|language]] are all copied from the Bourne shell, (<code>sh</code>). Other features, e.g., history, are copied from the [[C shell]], (<code>csh</code>), and the [[Korn Shell]], (<code>ksh</code>). It is a [[POSIX]]-compliant shell with extensions.