Shell Programming and Scripting

I had written a perl script to compare two files: new and master and get the output of the first file i.e. the first file: words that are not in the master file
STRUCTURE OF THE TWO FILES
The first file is a series of names
ramesh
sushil
jonga
sudesh
lugdi
whereas the second file (could be in Upper ASCII or Unicode has the following structureexamples are from UNICODE)
jonga=जोंगा
tuti=टूटी
namashi=नामषी
biruli=बिरुली
lugdi=लुगदी
sundi=सुंडी
hembram=हेंब्रम
hessa=हेस्सा
EXPECTED OUTPUT
What I need is to identify ONLY the new words in the new file
ramesh
sushil
sudesh
since jonga and lugdi are present in the master file, they will not be listed.

Both files,especially the master are big. I wrote a PERL script which I give belw, which does the job, but it too slow. Any way of improving it to speed up the process. I use Perl under Windows:
PERL SCRIPT FOLLOWS:

Code:

#!/usr/bin/perl

open $file1, $ARGV[0];
open $file2, $ARGV[1];
while ($l1 = <$file1>) {
    chomp $l1;
    while ($l2 = <$file2>) {
	if ($l2 =~ /^$l1\=/) {
	    $found = 1;
	    break;
	}
    }
    print "$l1\n" unless $found;
    seek $file2, 0, 0;
    $found = 0;
}

Where did things go wrong. I sorted the two files before using an Awk script. But the perl script is very slow and comparing two files: 30,000 words and 200,000 words takes an awful amount of time.
Many thanks in advance for speeding up the script

Moderator's Comments:

Please use code tags when posting code.

How about awk?

Code:

awk -F'=' 'NR==FNR{a[$1]++;next} !a[$1]' file2 file1

Dear Pravin27
I had written an awk script to do the job. But it was giving false positives when there was too much data.
Here is the script:
Practically the same as yours. When I had put it up, it was suggested to use an "O" for a large array:
BEGIN {FS="="}
NR==FNR{O[$1]++;next} !($1 in O)
Unluckily the script is fast but gives false positives, hence the PERL which gives correct positives but is slow.
I tried yours, it also gives false positives on a huge fle compare.
Manyt hanks.

Gimley

Hi, I hope this will run faster than your script.

Code:

#!/usr/bin/perl

open (F1, $ARGV[0]);
open (F2, $ARGV[1]);
while (<F2>) {
chomp;
$hash{(split(/=/))[0]}++;
}
while (<F1>) {
    chomp;
    next if $hash{$_};
    print $_,"\n";
}
close(F1);
close(F2);

Dear pravin27,
It runs very fast. As far as I can see there are no false positives. I'll check and get back only if there are no false positives.
I also understood the logic which speeds it up.
Many thanks for your kindness.
Gimley