Chapter 10: Installing Bash

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All of the following options except for ‘disabled-builtins’, ‘directpand-default’, and ‘xpg-echo-default’ are enabled by default, unless the operating system does not provide the necessary support.

--enable-alias

Allow alias expansion and include the alias and unalias builtins (see

Section 6.6 [Aliases], page 88).

--enable-arith-for-command

Include support for the alternate form of the for command that behaves like the

C language for statement (see Section 3.2.4.1 [Looping Constructs], page 10).

--enable-array-variables

Include support for one-dimensional array shell variables (see Section 6.7 [Ar- rays], page 89).

--enable-bang-history

Include support for csh-like history substitution (see Section 9.3 [History In- teraction], page 135).

--enable-brace-expansion

Include csh-like brace expansion ( b{a,b}c 7→ bac bbc ). See Section 3.5.1

[Brace Expansion], page 21, for a complete description.

--enable-casemod-attributes

Include support for case-modifying attributes in the declare builtin and as- signment statements. Variables with the uppercase attribute, for example, will have their values converted to uppercase upon assignment.

--enable-casemod-expansion

Include support for case-modifying word expansions.

--enable-command-timing

Include support for recognizing time as a reserved word and for displaying timing statistics for the pipeline following time (see Section 3.2.2 [Pipelines], page 8). This allows pipelines as well as shell builtins and functions to be timed.

--enable-cond-command

Include support for the [[ conditional command. (see Section 3.2.4.2 [Condi- tional Constructs], page 10).

--enable-cond-regexp

Include support for matching posix regular expressions using the ‘=~’ binary operator in the [[ conditional command. (see Section 3.2.4.2 [Conditional Con- structs], page 10).

--enable-coprocesses

Include support for coprocesses and the coproc reserved word (see Section 3.2.2

[Pipelines], page 8).

--enable-debugger

Include support for the bash debugger (distributed separately).