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Re: IO::Pipe hangs

by BrowserUk (Pope)
on Sep 20, 2012 at 19:14 UTC ( #994735=note: print w/replies, xml ) Need Help??


in reply to IO::Pipe hangs

Because you haven't emptied the pipe, which means that tasklist is blocked waiting to finish writing to it.

Just closing the pipe won't allow tasklist to end; the pipe won't close until it does. Deadlock.

The answer is to empty the pipe before closing it:

use strict; use warnings; use IO::Pipe; my $cmd = "tasklist"; my $pipe = IO::Pipe->new(); $pipe->reader($cmd); while (my $line = $pipe->getline()) { print $line; last if $line =~ /^smss/; } 1 while $pipe->getline; $pipe->close();

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Re^2: IO::Pipe hangs
by Anonymous Monk on Sep 20, 2012 at 19:16 UTC
    OK, thanks.