2006-10-31 15:23:16 +00:00
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\section psub psub - perform process substitution
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2005-10-21 12:39:45 +00:00
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\subsection psub-synopsis Synopsis
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<tt>COMMAND1 (COMMAND2|psub) </tt>
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\subsection psub-description Description
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Posix shells feature a syntax that is a mix between command
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substitution and piping, called process substitution. It is used to
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send the output of a command into the calling command, much like
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command substitution, but with the difference that the output is not
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sent through commandline arguments but through a named pipe, with the
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filename of the named pipe sent as an argument to the calling
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program. The psub shellscript function, which when combined with a
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regular command substitution provides the same functionality.
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\subsection psub-example Example
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<tt>diff (sort a.txt|psub) (sort b.txt|psub)</tt> shows the difference
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between the sorted versions of files a.txt and b.txt.
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