Just wrote a script:

Code:

$NAME = "Username"; # Example Variableopen(FILE, "member.dat"); # Filewhile() {$THIS_LINE=$_;chomp($THIS_LINE);if ($THIS_LINE eq $NAME) { print "You are already registered"; exit;}}close(FILE);open(FILE, ">>member.dat"); # Write file if user is not on the listprint FILE "$NAME\n";close(FILE);print "$NAME added to the list";exit; 

I hope that help you

Philipp's script looks good to me, but I see two small things to fix if you use this. For one, that exit; in the middle of the script leaves the file open - you should insert a close(FILE); right before it. Also, whenever opening files, it is good practice to verify that the file was opened properly. To do this, just add a die statement, i.e. open(FILE, "member.dat") or die "Error - Couldn't open member.dat: $!";
 
I'm sure you know these things Philipp - I just thought that as a PERL newbie he should be aware of them...

I used a little different method but it still works
 

Code:

open(FILE,"../www/roster_info/roster.txt");$exists++ if grep(/$name/i,(<FILE>));close(FILE);if ($exists) {print "Content-type: text/html\n\n"; print <<"EOF";<meta http-equiv="refresh" content="0;url=http://www.reservoirdogs.net/roster_info/already.shtml">EOF} else {

 
After the else I have the original contents of the script so it checks first, then it decides whether or not to actually register you (this is for a LAN party registration).
 
*EDIT*
Got the other part I needed done.