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From: Varun Chandramohan <varunc@linux.vnet.ibm.com>
To: ranjith kumar <ranjithproxy@gmail.com>
Cc: "linux-kernel" <linux-kernel@vger.kernel.org>
Subject: Re: how to read one udp packet with more than one recvfrom() calls?
Date: Tue, 9 Nov 2010 11:05:55 +0530	[thread overview]
Message-ID: <201011091105.56137.varunc@linux.vnet.ibm.com> (raw)
In-Reply-To: <AANLkTi=40758wF4Z6GDfm809miA-hnCnSQdwA9bALX0+@mail.gmail.com>

try MSG_PEEK option.

Regards,
Varun 

On Monday, November 08, 2010 12:38:47 pm ranjith kumar wrote:
> Hi,
> 
> I  have implemented client and server programs using udp
> protocol(files are attached).
> UDP packet size is 500bytes.
> 
> I want to read these 500bytes in two calls to recvfrom(). First time
> reading 100bytes and second time 400bytes.
> How to do this?
> 
> When I tried to change the third argument of recvfrom(size_t len),
> from 500 to 100, first 100bytes are read correctly.
> But when I call recvfrom() second time with len=400, it is reading the
> first 400bytes of "next udp packet".
> Why? Isn't it possible to read one udp packet in two calls to
> recvfrom()/read()????
> 
> Thanks in advance.
> 

      parent reply	other threads:[~2010-11-09  5:36 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-11-08  7:08 how to read one udp packet with more than one recvfrom() calls? ranjith kumar
2010-11-08  7:12 ` Changli Gao
2010-11-08  7:51 ` Michael Tokarev
2010-11-08 18:31 ` Rick Jones
2010-11-09  5:35 ` Varun Chandramohan [this message]

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