I think you need to use select on your pipe. Here is an example. 
#!/usr/bin/perl -w
use strict;
use IPC::Open2;
use IO::Select;
$| = 1; # autoflush STDOUT

# Declare filehandles and command to use:
my ($r, $w);
my $cmd = 'ping 127.0.0.1';

# Open the process and set the selector:
my $pid = open2($r, $w, $cmd);
my $selector = IO::Select->new($r);

while (1)  # infinite loop (use "last" to break out)
{
if ($selector->can_read(0))
{
my $chars;
my $bytes_read = sysread($r, $chars, 4046);
print "$bytes_read $chars\n";
}

# Do anything you want in between reads here...
}

__END__

#by J. Romano

# The advantage to this script is that, if your commands (like
# "whois", "dig", and "ping") happen to pause, the loop won't
# automatically break out.  The disadvantage to this script is that it
# might be difficult figuring out when a command has finished, or just
# has delayed output (in which case you might have to put in a few
# sleep() calls).  Either way, I think that this script here does a
# better job of helping you visualize what is going on -- you just nee
+d
# to be mindful of the fact that some programs don't flush their outpu
+t
# right away, and that it's not a simple matter to tell if the program
# has stopped running altogether.

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In reply to Re: Premature close of the pipe by zentara
in thread Premature close of the pipe by Superfox il Volpone

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