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Re: Clarification in man page for CURLOPT_WRITEFUNCTION for nmemb==0

From: Daniel Stenberg via curl-library <>
Date: Thu, 23 May 2019 23:29:45 +0200 (CEST)

On Thu, 23 May 2019, Nicolas Roeser via curl-library wrote:

> | This function may be called with zero bytes data if the transferred
> | file is empty.
> Ahh, good to know. But _still_, I am not sure whether the function may be
> called with 0 bytes _if the transferred file is *not* empty._

I think it doesn't specifically specify that because we haven't wanted to make
that promise. Partly because it seems that applications don't really *need*
that promise and people have not asked for it. Until now.

> 3) Depending on the protocol [or something else], this function may or will
> never be called with zero bytes if the transferred file is not empty.

I want to say this as that's basically what is implied now and it makes the
least amount of promise and we don't have to change anything... =)

This said, I don't think it currently actually ever calls the callback with
zero bytes other than the specific use case already mentioned above!

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Received on 2019-05-23