#!perl -w
# self-contained counter script increments and prints value in DATA
# set permissions to allow script to read and write itself - epoptai

use strict;

my$e = 0;
my$d;

while(<DATA>){$d .= $_} # read data
$d++; # increment

open (ME,"+>> $0") or die "$!"; # open self
unless($^O=~/mswin/i){ flock(ME,2) or die "$!"} # lock unless win32
my@me = <ME>; # read self into array

for(@me){
	if($_=~m|_\_DATA_\_|){ $e = 1; next } # find last line
	if($e == 1){ $_ =~ s/\d+/$d/o } # and replace with incremented value
	}
seek ME, 0, 0; # goto top of self
truncate ME, 0; # and clear it
print ME @me; # write modified contents
close ME or die "$!";

print $d; # print incremented value

__DATA__
0