Hi monks

Are common (ie not obviously OS specific) $! error codes portable?

In particular, I need to check for non existant files - rather than introduce a (small) race condition by something like: 


  return unless -f $file;

  open INFILE, "<", $file or die "open failed: $!";
I'd prefer to check $! after open fails, say: 

  unless ( open INFILE, "<", $file )
  {
    return if $! + 0 == 2;
    die "open failed: $!";
  }
The crux of the issue is that I assume 2 is the correct error code for "no such file". On linux and Win32, this is true, but can I safely assume this is true on other platforms? If anyone can show me where in the 5.8 source I can find $! codes defined, that would be even better.

Thanks for your help

In reply to How portable are common $! error codes? by Anonymous Monk

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