since people can submit forms by hitting Enter on a text field, in which case the named submit button isn't referenced.

Just FWIW, last I heard, only IE does that. The other browsers will send a submit argument.

As for what to do to avoid that, I either check that the request is POST, or check for a required param's existence. If the request does something that is not read-only (like the OP's script seems to do), I'd very strongly consider changing the form submission to POST from GET.

In reply to Re^2: Web form to alter files is writing to file before submit button is pressed. by Anonymous Monk
in thread Web form to alter files is writing to file before submit button is pressed. by Lady_Aleena

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