I would change things such that you stuff the ps output into an array, rather than a single string: 
@outlines = `ps -ef | grep $logname`;

[download]

Then, I would capture what you want with the regex, not the pre-match. Note that you can avoid excessive escaping in the regex by using alternate delimiters, m{}: 

use strict;
use warnings;

my $logname = 'mylogname';
while (<DATA>) {
    if (m{(.*/export/home/$logname)/.*/bin/.*}) {
        print $1, "\n"
    }
}

__DATA__
root 28834 28833 0 Aug25 ? 00:00:00 login -- mylogname2
root 29853 29852 0 Aug25 ? 00:00:00 login -- mylogname2
root 5379 5378 0 Aug26 ? 00:00:00 login -- mylogname2
root 5454 5453 0 Aug26 ? 00:00:00 login -- mylogname2
509 6710 1 0 00:20 ? 00:00:28 /export/home/mylogname/folder1/bin/binar
+y
509 6729 1 0 00:35 ? 00:00:11 /export/home/mylogname/folder2/bin/binar
+y
522 7996 1 0 07:00 ? 00:00:07 /export/home/mylogname2/folder1/bin/bina
+ry
509 7997 1 0 07:00 ? 00:00:01 /export/home/mylogname/folder3/bin/binar
+y
522 8045 1 0 07:02 ? 00:00:02 /export/home/mylogname2/folder4/bin/bina
+ry

[download]

prints: 

509 6710 1 0 00:20 ? 00:00:28 /export/home/mylogname
509 6729 1 0 00:35 ? 00:00:11 /export/home/mylogname
509 7997 1 0 07:00 ? 00:00:01 /export/home/mylogname

[download]

Is this the output you are looking for?

Update: Please re-read How do I compose an effective node title?.

In reply to Re: Retrieve "ps -ef" strings using regex by toolic
in thread Retrieve "ps -ef" strings using regex by Raoul

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