in reply to Copy STDOUT and STDERR to logfile and also display to screen

If you are on non UNIX platform i wrote this small script that does tee - useful with pipes: Creating an outputfile and processing it at once

tee is useful when you cannot change the script that was given to you and you want to save and view. But if you are the author of the script why can't a simple print statement work?

for example - 

if ($error) {
   print STDERR ("Error: $errmsg\n");
   print ERRLOG ("Error: $errmsg\n");
} else {
   print ("Output: $outstr\n");
   print CLEANLOG ("Output: $outstr\n");
}

[download]

Of course if you if you are interpolating the string inside print I would probably first do that in a variable and use it inside print to avoid interpolating twice

Am i missing somethign here?

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Re^2: Copy STDOUT and STDERR to logfile and also display to screen
by Fletch (Bishop) on Aug 10, 2005 at 17:54 UTC

    It works, but now you've got two copies of every message. At the very least wrap that up in a pair of subs. 

    sub my_print { print @_; print CLEANLOG @_ }
sub err_print { print STDERR @_; print ERRLOG @_ }

    [download]

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[d/l]
      Thanks for the tip on the sub.

      regarding your other comment: It works, but now you've got two copies of every message

      Could you please explain what do you mean by copy? it writes the same msg twice but it does it in two different places...the output on the screen will not have dups and the output in the log will not have dupliactes...

      if you say it is inefficient to do it this then i would agree but i am not sure whether i understand the term "copy" there.

      thanks

      SK

[reply]

        In your code you have to duplicate two copies of every message you print in your source; if you ever need to change the output you'd have to edit each copy of each pair of prints. It's left as an exercise to imagine the fun that commences when one or more inevitably gets out of sync and you have different results in different places for the "same" output. To say nothing of 7 months down the line when marketing wants the output also sent to a third and fourth place . . .

        Using the subs (or the IO::Tee module or tee externally) you have to change just one string to affect the output to every destination.

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