Sep 22, 2020 · Bash is the GNU Project's shell—the Bourne Again SHell. This is an sh-compatible shell that incorporates useful features from the Korn shell (ksh) and the C shell (csh).

The following menu breaks the features up into categories, noting which features were inspired by other shells and which are specific to Bash. This manual is meant as a brief introduction to features found in Bash. The Bash manual page should be …

Jul 4, 2025 · This manual (bash) is available in the following formats: HTML (1020K bytes) - entirely on one web page. HTML - with one web page per node. HTML compressed (192K gzipped characters) - entirely on one web page. HTML compressed (228K gzipped tar file) - with one web page per node. Info document (168K bytes gzipped tar file).

May 18, 2025 · The following menu breaks the features up into categories, noting which features were inspired by other shells and which are specific to Bash. This manual is meant as a brief introduction to features found in Bash. The Bash manual page should be used as the definitive reference on shell behavior.

If the operating system on which Bash is running provides these special files, Bash uses them; otherwise it emulates them internally with this behavior: If the file argument to one of the primaries is of the form /dev/fd/N, then Bash checks file descriptor N.

If Bash is started with the -c option (see Invoking Bash), then $0 is set to the first argument after the string to be executed, if one is present. Otherwise, it is set to the filename used to invoke Bash, as given by argument zero.

Bash is the shell, or command language interpreter, for the gnu operating system. The name is an acronym for the ‘Bourne-Again SHell’, a pun on Stephen Bourne, the author of the direct ancestor of the current Unix shell sh, which appeared in the Seventh Edition Bell Labs Research version of …

Bash uses the value formed by expanding the rest of parameter as the new parameter; this new parameter is then expanded and that value is used in the rest of the expansion, rather than the expansion of the original parameter. This is known as indirect expansion.

Show version information for this instance of Bash on the standard output and exit successfully. There are several single-character options that may be supplied at invocation which are not available with the set builtin.

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