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Use tee to process a pipe with two or more processes

Terminal - Use tee to process a pipe with two or more processes
echo "tee can split a pipe in two"|tee >(rev) >(tr ' ' '_')
2010-08-14 20:38:59
User: axelabs
Functions: echo tee tr
33
Use tee to process a pipe with two or more processes

Tee can be used to split a pipe into multiple streams for one or more process to work it. You can add more " >()" for even more fun.

Alternatives

There are 2 alternatives - vote for the best!

Terminal - Alternatives
tee >(cat - >&2)
2010-07-20 17:22:31
User: camocrazed
Functions: cat tee
5

the tee command does fine with file names, but not so much with file descriptors, such as &2 (stderr). This uses process redirection to tee to the specified descriptor.

In the sample output, it's being used to tee to stderr, which is connected with the terminal, and to wc -l, which is also outputting to the terminal. The result is the output of bash --version followed by the linecount

Know a better way?

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What others think

Cool trick!

Unfortunately Cygwin has a bug in 1.7 that prevents this from working. AIX also has problems with it - it runs once but hangs after that. I thought it was leaving pipes around but it still hangs if I delete them from /tmp. Any help is much appreciated.

Comment by randy909 263 weeks and 3 days ago

My debian show this error: tee: /dev/fd/63: File or directory not found

Comment by n158 139 weeks ago

Here is the magic behind it:

http://tldp.org/LDP/abs/html/process-sub.html

Comment by axelabs 127 weeks ago

Your point of view

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