For speed, you might do simple checks first, and only do an md5 check if the file size and simple crc check is identical. You can also test just the first few thousand bytes of a file, instead of running crc or md5 on the entire file. 
#!/usr/bin/perl
use warnings;
use strict;

# same as "sum -s file"   use System V sum algorithm, use 512 bytes bl
+ocks

my $buf; 
open (FH,"< $0");
read( FH, $buf, -s FH );
close FH;

my $checksum = unpack("%32C*",$buf) %32767;  

print "$checksum\n";

exit;

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I'm not really a human, but I play one on earth.
Old Perl Programmer Haiku ................... flash japh

In reply to Re: [OT]:Faster signature algorithm than md5? by zentara
in thread [OT]:Faster signature algorithm than md5? by swampyankee

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