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From: leo@atcmp.nl (Leo  Willems)
Newsgroups: comp.unix.questions
Subject: Re: Piping stderr in Korn and/or Bourne shell
Message-ID: <585@atcmpe.atcmp.nl>
Date: 7 Apr 90 19:22:35 GMT
References: <3620@hcx1.SSD.CSD.HARRIS.COM>
Organization: AT Computing, Nijmegen, The Netherlands
Lines: 32

From article <3620@hcx1.SSD.CSD.HARRIS.COM>, by brad@SSD.CSD.HARRIS.COM (Brad Appleton):
> 
> I have a program that is supposed to read error output from other
> programs. I want to pipe stderr to this program WITHOUT piping
> stdin as well. I have not been able to find this in TFM (I have 
......
> I was hoping one of these last two might give me the output:
> 
>     this is stdout
>     this is STDerr
> 
> without piping stdin at all (just stderr)

Try this:

prog 3>&2 2>&1 1>&3 3>&- | sed 's/std/STD/'

This will swap stdout/stderr.

If you know a little C under UNIX it says:

prog close_3_dup_2 close_2_dup_1 close_1_dup_3 close_3 | sed


Hope this helps.


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