It's been my experience that the POST data to Apache mod_cgi-based programs is delivered "live" and not buffered. (As an aside, that's why you can't rely on reading "content-length" number of bytes, because that's only what the browser suggested it was going to send.)
in reply to Direct access to client socket in CGI/mod_perl?
However, I have to ask the next question: how will your CGI know when the data is actually finished then?
Also, if there are any proxies in between, all bets are off.
-- Randal L. Schwartz, Perl hacker
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