readv: parallel or sequential?

[Poul-Henning Kamp]

In message <fjbh4h$f5s$1 at ger.gmane.org>, Ivan Voras writes:
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>Dag-Erling Sm=C3=B8rgrav wrote:
>
>> But to return to what Ivan was asking, I think what the man page is
>> trying to say is that you can't use readv() to e.g. read individual
>> network packets into separate buffers (unless each packet just happens
>> to fit exactly within each buffer).
>
>What about streaming protocols like TCP? If, for example, I know I have
>a N-byte header, N2-byte body, couldn't readv handle it with two iovecs?

yes.

>But that's not why I started the discussion. I'm looking for a way to do
>"scattered" async IO on files (the intention: feed an array of offsets,
>lengths and buffers into the kernel, let it perform the requests in
>parallel, if it can) and started with this man page.

You want AIO

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Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
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