Ok, I apologise if I'm being overly dense, but I don't get what you're actually asking.
Executing the CGI as above would enable 1.pl to grab the filename, and use it to it's own nefarious ends.
If this file contains data for a menuing system, then the rest is merely generic programming.
If you need the data from the execution of 1.pl placed in another file, you can use string manipulation to add a prefix/other suffix to use filenam.txt as your root, so you know what the final file relates to.
If it's just a generic file, think of a name and open(F,">/blah/otherfile");print F "other data";close F;
Again, apologies if I've missed the point entirely, but this is simply where reading your specification of the problem leads my thinking.

Malk
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