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#!/opt/i386-linux/perl/bin/perl -w

## Submitted by Blair Zajac <blair@orcaware.com>

## Tests blocking when piping though a &sub coprocess.
## Fixed, now in test suite.

$| = 1;

use strict;
use Carp;
use Symbol;
use IPC::Run                  0.44 qw(start);

print "My pid is $$\n";

my $out_fd = gensym;
open($out_fd, ">ZZZ.test") or
  die "$0: open: $!\n";

my $queue = '';

my @commands = ([['cat', '-'], \$queue, '|'], 
                [['cat'],  '|'], 
                [\&double, '>', $out_fd]); 

my $harness = start 'debug' => 10, map { @$_ } @commands;
$harness or
  die "$0: harness\n";

close($out_fd) or
  die "$0: cannot close: $!\n";

for (1..100) {
  $queue .= rand(100) . "\n";
  $harness->pump;
}
$harness->finish or
  die "$0: finish\n";

exit 0;

sub double {
  while (<STDIN>) {
    s/\s+$//;
    print "$_ $_\n";
  }
}