in reply to stderr output

Redirection in NT is accomplished much like in Unix.
Redirecting STDOUT is done with > or 1>, redirecting STDERR
with 2>.

For example 

n:\>ls c:\foo
ls: c:/foo: Not a directory

n:\>ls c:\foo 2> c:\tmp\error.txt

n:\>more c:\tmp\error.txt
ls: c:/foo: Not a directory

n:\>

[download]
However, in this precise instance, I think you would be
better off fixing the source of the error, in this
case, exiting a subroutine with next. You should use
return to exit a subroutine, not next, which is use for
going to the next item in a loop.

Regards,
Helgi Briem

Replies are listed 'Best First'.
Re: Re: stderr output
by Anonymous Monk on Sep 09, 2002 at 18:16 UTC
    Thanks it works. Questions: What does "return" do different compared to "next" in a subroutine? Also does the way I did my return part look okay? The error output (Exiting subroutine via next at C:\Perl\bin\myscript.pl line 188.) never comes up in my text file (bas.txt) for some unknown reason? 
      if ($data =~ /patternmatch/i)
    {
        open FILY, ">bas2.txt";
        print FILY "Skip $data\n";
        return ">bas2.txt";
    }

    [download]
[reply]
[d/l]
[select]
      next is for loop control while return is for returning from a subroutine. Witness the different behaviour in this (demonstration only) code: 
      mysub(5);

sub mysub {
  my $val = shift || 8;
    
  print "next demo: \n";
  for (1..10){
    next if $_ == $val;
    print $_, "\n";
  }
  print "\nreturn demo: \n";
  for (1..10){
    return if $_ == $val;
    print $_, "\n";
  }
}

      [download]

      --
      Until you've lost your reputation, you never realize what a burden it was or what freedom really is. -Margaret Mitchell

[reply]
[d/l]
        Thanks for the detailed explanation! Now I understand.
[reply]

       if ($data =~ /patternmatch/i)
  {
    open FILY, ">bas2.txt";
    print FILY "Skip $data\n";
    return ">bas2.txt";
  }

      [download]

      Just so that we don't steer you wrong, could you tell us what you think this piece of code is doing? Just a plain english description will do.

      It might also be advantageous to you to post a little more of your code, including the rest of this subroutine, and the part where it is called.

      Well It's better than the Abottoire, but Yorkshire!
[reply]
[d/l]
[select]

In Section Seekers of Perl Wisdom