G'day brianMonk,

Welcome to the monastery.

Here's another way to do it. While this is a working script, it's really just skeleton code. You may want to add feedback about whether the supplied username was found as well as a confirmation of the deletion.

#!/usr/bin/env perl

use strict;
use warnings;
use autodie;

my ($user_file, $changed_file) = qw{test.txt test.txt.mod};

open my $in_fh, '<', $user_file;
open my $out_fh, '>', $changed_file;

print 'Enter user to delete: ';
chomp(my $user = <>);

while (<$in_fh>) {
    print $out_fh $_ unless /^\Q$user\E,/;
}

close $in_fh;
close $out_fh;
rename $changed_file, $user_file;
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