[En-Nut-Discussion] Question about CGI

[Ole Reinhardt]

Hi,

> Yes this might be the cause, but how can I check if the file (stream) 
> descriptor is still valid ?

You simply should check the return values of every function that support
return values (like fputc).

> I tried also to hit "stop" button of my browser before file transfer 
> finishes. In such situation my function still writes to the stream but 
> there is no restart - write() simply returns some error code, my cgi 
> function returns and everything is ok.

Ok. So the closed file descriptors does not seem to be a problem. Next
problem could be that the cgi function is called more the once (if you
allow more than one httpd thread at a time.) In this case your cam
functions will be called more than once too. I doubt they are reentrant,
so this will be a problem. Use a mutex to lock the cam communication.

Bye,

Ole
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