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-
- NAME
- tpipe - replicate the standard output into an additional
- pipeline that is run in a subshell
-
- SYNOPSIS
- tpipe [ pipeline ]
-
- DESCRIPTION
- tpipe transcribes the standard input to the standard output and
- simultaneously writes an additional copy to a specified
- pipeline.
-
- tpipe is similar to tee(1) except that tpipe writes the
- duplicate copy of its standard input to a command or pipeline
- instead of a file. This can help you avoid re-executing earlier
- commands in the pipeline, writing temporary files, or resorting
- to the use of named pipes.
-
- The specified pipeline is always executed in a subshell by
- sh(1), regardless of your current shell. If a non-empty string
- is supplied as the argument, it must be a valid pipeline or
- command for sh(1). Normally, you will want to enclose the
- pipeline argument in quotes ('' or ""). The type of quotes you
- choose will affect variable substitution by your shell (see the
- man page for your shell, such as csh(1), for details).
-
- If the subshell pipeline writes to its standard output, this
- output will go to the standard output of tpipe, where it will be
- interspersed in an unpredictable way with the other copy of
- standard input. Normally, this is not what you want. Instead,
- you would typically specify a subshell pipeline whose output is
- redirected to a file (as in the example below) or has some other
- effect.
-
- EXAMPLE
-
- % cmd1 <infile | tpipe "cmd2 | cmd3 >outfile" | cmd4
-
- which has the effect of running the output of command cmd1
- simultaneously through two pipelines, "cmd2 | cmd3 >outfile" and
- cmd4. Diagramatically, in this example (this will look wrong
- with a variable-spaced font):
-
- --> cmd2 --> cmd3 --> outfile
- /
- infile --> cmd1 -<
- \
- --> cmd4 --> (standard output)
-
- SEE ALSO
- tee(1), sh(1), cat(1)
-
- AUTHOR
- David B Rosen
-
- THIS SOFTWARE IS PROVIDED "AS IS" AND WITHOUT EXPRESS OR IMPLIED
- WARRANTY.
-
-