The webserver should normally terminate the CGI script in case the browser prematurely closes the connection.  So, you could try putting your cleanup code in an END { ... } block, which should execute upon termination of the CGI script.

In case that doesn't work, you'll probably also have to set up a signal handler (most likely for SIGTERM, but I haven't checked1) calling die or exit, which in turn will make the script terminate in a controlled fashion, so the END block executes.  (Details depend on the webserver, OS, etc.)

___

1 in a private msg Perlbotics noted (thanks!) that according to his observations, it would rather be SIGPIPE — which makes perfect sense, as the script would be trying to output to a broken pipe (presuming it hasn't already finished writing at the time...).

In reply to Re: How to ensure to close the opened files in cgi if browser is closed by almut
in thread How to ensure to close the opened files in cgi if browser is closed by chinu_regal

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