#! /usr/bin/perl -w
use strict;

# read the file
open FH , "<" , "/etc/mtab" or die "can't open file";
my @line_list = <FH>;
close FH;

# count the number of "/home" "nfs" lines
my $match_count = grep { m/ \/home nfs / } @line_list;
if ($match_count == 0) {

    print "Do something\n";

} else {

    print "DO something different\n";
}