Why don't you just save the original in a temp file? $0 can get messed with, but if you read it first thing, and write it to a file, then you can just read the file. It works for PIDs, anyway...

Paris Sinclair    |    4a75737420416e6f74686572
pariss@efn.org    |    205065726c204861636b6572
I wear my Geek Code on my finger.