How to use ``nice'' on a pipe?

[Wei Chen <wchenhk@gmail.com>]

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Hi,

I usually use ``nice'' and ``ionice'' to run a program in a low
priority. But with the following script, I only get command1 running in
a low priority. How can I make both command1 and command2 on the pipe
running in the low priority? Thank you.

=================================
#!/bin/sh
runprogram () {
  nice -n19 ionice -c2 -n7 "$@"
}
runprogram command1 | command2
=================================

- --
Cheers,

Wei Chen
http://www.acplex.com/people/wchen/
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