#!/usr/bin/perl

use strict;

my @ids = qw( john james );
my $permission = get_data( q{^$_}, @ids );
print $permission;

my $permission = get_data( q{"\\b$_\\b"}, @ids );
print $permission;

sub get_data {
    my ($pattern, @ids) = @_;
    my $permission;

    for (@ids) {
        $permission = qx( grep $pattern /etc/passwd );
    }
    return $permission;
}