I tried to get at the problem by having the relevant CGI script open a file, and write diagnostic info to that, but when I access the page after doing that, no such file is created.

There are 2, possibly more, causes: 1) the opening of and printing to the filehandle is being done in some type of conditional block which is not being triggered or 2) the open call is failing and you don't have any error checking/handling on that call.

In reply to Re: How to get diagnostic information for a web app when nothing is written to the error log by fishmonger
in thread How to get diagnostic information for a web app when nothing is written to the error log by ted.byers

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