Thanks for your suggestions Joost. I had already tried the die "......$!" before I posted my original message. It didn't help because I'm testing this on a web server, through a browser, and the page I'm generating just terminates at the point of error without reporting the error. I also don't seem to have access to the error_log on this particular (institutional) server.

Tilly (see below) hit on the cause of the problem. Just to follow up on your suggestion, I ran the script from a command line and got another confirmation that it was the taint checking: 
    Insecure dependency in unlink while running with -T switch at ./de
+lete.cgi line 43.

[download]
Thanks again.

In reply to Re^4: Why aren't these equivalent? by Anonymous Monk
in thread Why aren't these equivalent? by Anonymous Monk

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