I still don't get locking. I just want to increment the number in the file. How can I do this?

Anyway, this is what to do:

    sysopen(FH, "numfile", O_RDWR|O_CREAT, 0644) or die "can't open numfile: $!";
    flock(FH, 2) 				 or die "can't flock numfile: $!";
    $num = <FH> || 0;
    seek(FH, 0, 0) 				 or die "can't rewind numfile: $!";
    truncate(FH, 0) 				 or die "can't truncate numfile: $!";
    (print FH $num+1, "\n")			 or die "can't write numfile: $!";
    # DO NOT UNLOCK THIS UNTIL YOU CLOSE
    close FH 					 or die "can't close numfile: $!";

Here's a much better web-page hit counter:

    $hits = int( (time() - 850_000_000) / rand(1_000) );

If the count doesn't impress your friends, then the code might. :-)

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