From: Johannes Sixt <j6t@kdbg.org>
To: Antoine Pelisse <apelisse@gmail.com>
Cc: Junio C Hamano <gitster@pobox.com>,
Git Mailing List <git@vger.kernel.org>
Subject: Re: [PATCH] stream_to_pack: xread does not guarantee to read all requested bytes
Date: Tue, 20 Aug 2013 20:27:59 +0200 [thread overview]
Message-ID: <5213B52F.7030205@kdbg.org> (raw)
In-Reply-To: <CALWbr2yaQaCte6+Y3GEa8Hxyhq6GPS64aTNzkGo8pdpcd9ZVUg@mail.gmail.com>
Am 20.08.2013 17:16, schrieb Antoine Pelisse:
> I was actually wondering when it's better to use xread() over
> read_in_full() ? Considering that we don't know if xread() will read
> the whole buffer or not, would it not be better to always use
> read_in_full() ?
Of course, you know whether the whole buffer was filled: xread() returns
the number of bytes read. Same for xwrite().
> I guess there is a drawback to this, but I'm not
> exactly sure what it is.
The disadvantage of read_in_full() is that it can happen that it reads
data from the stream successfully, but then reports an error. In this
case, the data read is lost.
Analogously, when write_in_full() writes (some) data successfully, but
ultimately fails, you don't know how much was written successfully.
-- Hannes
next prev parent reply other threads:[~2013-08-20 18:28 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-08-20 9:15 [PATCH] stream_to_pack: xread does not guarantee to read all requested bytes Johannes Sixt
2013-08-20 15:00 ` Junio C Hamano
2013-08-20 15:16 ` Antoine Pelisse
2013-08-20 18:27 ` Junio C Hamano
2013-08-20 18:27 ` Johannes Sixt [this message]
2013-08-20 18:23 ` Johannes Sixt
2013-08-20 18:52 ` Junio C Hamano
2013-08-20 19:37 ` Johannes Sixt
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