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From: jik@athena.mit.edu (Jonathan I. Kamens)
Newsgroups: comp.unix.internals,comp.unix.questions
Subject: Re: Redirection of stderr
Keywords: stderr
Message-ID: <1991Mar14.220650.11736@athena.mit.edu>
Date: 14 Mar 91 22:06:50 GMT
References: <574@dprmpt.UUCP>
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In article <574@dprmpt.UUCP>, larry@dprmpt.UUCP (Larry) writes:
|> In a C program, how can I change stderr from wherever it is directed
|> via the command line to a file, then later revert it back to it's 
|> original destination?

  This is not a comp.unix.wizards question.  I have cross-posted this response
to comp.unix.questions and directed followups there.

  First, "stderr_fd = dup(fileno(stderr))" to preserve the original stderr
output direction.  Then "fclose(stderr)", and immediately do "stderr =
fopen(your_stderr_file, "w")" (the "immediately" is so that the newly opened
file will get the same file descriptor stderr had, in case you've got that
file descriptor hard-coded somewhere in your code).  When you're done,
"fclose(stderr)" and do "stderr = fdopen(stderr_fd, "w")" to put things back
the way they were originally.

-- 
Jonathan Kamens			              USnail:
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