scripted piped system commands

From: Deb (beginners_at_perl.org)
Date: 12/31/03 

Date: Wed, 31 Dec 2003 07:55:29 -0800
To: Perl List <beginners@perl.org>

Happy Almost New Year!

I want to run a unix system command inside a script. From the
shell, here's the command(s):

% ps -ef | /bin/egrep '/usr/lib/sendmail' | /bin/grep -v grep | /bin/awk '{print $2}'
19460

What is returned is the pid of the process being grep'd.

But, when I put this into a test script,

---- snip ----

my $pid = `ps -ef | /bin/egrep '/usr/lib/sendmail' | /bin/grep -v grep | /bin/awk '{print $2}'`;
print "\$pid is: $pid \n";

---- snip ----

And, here's the output:

$pid is: root 19460 1 0 Dec 18 ? 0:08 /usr/lib/sendmail -bd
-q15m

It seems to be only going as far as dropping off the grep (grep -v),
and never executing the awk '{print $2}'. I've tried this with
the system() call, with the same results.

Please, what am I missing? :-(

deb

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