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36 lines
746 B
Markdown
36 lines
746 B
Markdown
# Grouping commands in a subshell
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## Synopsis
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( <LIST> )
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## Description
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The [list](/syntax/basicgrammar#lists) `<LIST>` is executed in a
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separate shell - a subprocess. No changes to the environment (variables
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etc...) are reflected in the "main shell".
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## Examples
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Execute a command in a different directory.
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``` bash
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echo "$PWD"
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( cd /usr; echo "$PWD" )
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echo "$PWD" # Still in the original directory.
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```
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## Portability considerations
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- The subshell compound command is specified by POSIX.
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- Avoid ambiguous syntax.
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``` bash
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(((1+1))) # Equivalent to: (( (1+1) ))
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```
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## See also
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- [grouping commands](/syntax/ccmd/grouping_plain)
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- [Subshells on Greycat's wiki](http://mywiki.wooledge.org/SubShell)
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