foreach my $line (@file) {
        chop ($line);
        $line =~ s/ //g;
        my @values = split (/,/, $line);
        $thehash{$values[$field]} .= "$line\n";
}

##</code><code>##

@keys = sort(keys %thehash);
foreach (@keys) {
        print "$thehash{$_}";
}