The problem is you're reading the file one line at a time. If you find a blank line, you're essentially replacing it with another blank line, so there's no net change. If you process it one line at a time, you need to write nonblank lines out to a separate file as you go, so it will have the nonblanks when you're done. If you know the file won't be too big, I think you could also use this regex: 
$entire_file =~ s/^\n$//mg;

[download]
That should leave $entire_file with only nonblank lines. HTH.

In reply to Re: replacing blank lines by Anonymous Monk
in thread replacing blank lines by indapa

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