#!/usr/bin/perl

$LOCK_SH = 1;
$LOCK_EX = 2;
$LOCK_NB = 4;
$LOCK_UN = 8;

sub lock {
  flock (LOCKFILE,$LOCK_EX);
  seek (LOCKFILE,0,2);
}

sub unlock {
  flock (LOCKFILE,$LOCK_UN) ;
}

print "Content-type: text/shtml\n\n";

open (LOCKFILE,"<_count_lock");       # open lock file 

lock;                                 # lock file

open (GETCOUNT,"<count.log");         # open count log for input 
$counter=<GETCOUNT>;                  # assign contents of file to $counter 
close (GETCOUNT);                     # close access to file 

$counter++;                           # increase $counter by 1. 
print "<H1>";
print "$counter";                     # print number of hits to users screen 
print "</H1>";

open (PUTCOUNT,">count.log");         # open count log for output 
print PUTCOUNT ($counter);            # replace old counter value with new one 
close PUTCOUNT;                       # close access to file 

unlock;                               # unlock file

close LOCKFILE;                       # close lock file