Description:
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http_send_file returns 1 even when a stream has been interrupted.

Reproduce code:
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Just http_send_file any large file and hit stop, it will return 1.

Expected result:
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Well, for http_send_file I would expect it to return 1 on successfully sending the entire file _or_ successfully sending an entire range request. For http_send_data I would expect a 1 for successfully sending any random amount of data.

It's current operation makes it impossible to tell when a completely sucessful request has been completed.  This is important for something like a download counter for instance which is probably one of the largest reasons you would send a file through php and not statically serve it.

I would suggest keeping it's current operation and add a flag to change the meaning of the return value.  And as a purely 'feature-request' another flag to return an array of bytes-requested (0 for all) and the 2nd value being bytes sent, and a final flag for just bytes-sent.

Feel free to file this as a feature-request but I do honestly belive it to be a bug.