I have the following piece of code to track a log-file.

I search for a pattern e.g. /Some pattern/, and come out when i get one.

open PIPE, "-|", "/usr/bin/tail", "-f", "$perf_logfile"
   or die "could not start 'tail' on $perf_logfile: $!";

[download]
while (<PIPE>) {
    if ( $_ =~ /(Some pattern)/i ) {
        print("- $1 encountered");
        last;
    }
}
close PIPE;

[download]

This was resulting in...

/usr/bin/tail: write error: Broken pipe

/usr/bin/tail: write error

as I close the pipe, even when 'tail' is pouring its heart's content into it.

I knew the problem but decided to live with it as this was the closest best to what i wanted, with a simple implementation.

Lately i have seen it resulting in hangs in the 'close PIPE' statement; after i had a change in my workspace.

Question :

Is there a way to send CRTL-C to the /tail/ process ?

before I try and close the pipe associated with it.

Am hoping in that way i won't be seeing the hangs/errors.

Why does it work in some cases and not in another ? What does this typically depend on ?

In reply to pipe-ing the 'tail' results in 'broken pipe' by angshuman

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