Editing Bash (Unix shell) (section)

=== Control Structures ===
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'''+++ <code>if</code>'''

'''+++ <code>case</code>'''

'''+++ <code>for</code>'''

'''+++ <code>for ((</code>'''

'''+++ <code>while</code> and <code>until</code>'''

'''+++ <code>&&</code> and <code>||</code>'''
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Bash supplies "conditional execution" command separators that make execution of a command contingent on the [[Exit status|exit code]] set by a precedent command. For example:

<syntaxhighlight lang="bash">
cd "$SOMEWHERE" && ./do_something || echo "An error occurred" >&2
</syntaxhighlight>

Where {{code|./do_something}} is only executed if the {{code|cd}} (change directory) command was "successful" (returned an exit status of zero) and the {{code|echo}} command would only be executed if either the {{code|cd}} or the {{code|./do_something}} command return an "error" (non-zero exit status).

For all commands the exit status is stored in the special variable <code>$?</code>. Bash also supports {{code|2=bash|if ...;then ...;else ...;fi}} and {{code|2=bash|case $VARIABLE in $pattern)...;;$other_pattern)...;; esac}} forms of conditional command evaluation.
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=== Boolean Testing ===
'''+++ <code>test</code> Built-In and Binary'''

'''+++ Single Bracket <code>[</code> Built-In and Binary'''

'''+++ Double Bracket <code>[[</code> Built-In (and no Binary)'''
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=== Pipelines ===
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=== Subshells ===
'''+++ Standard Subshells <code>(...)</code>'''

'''+++ Command Substitutions <code>$(...)</code>'''

'''+++ Pipelines (again) <code>| ... |</code>'''
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=== Signals ===
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