tcpdump mailing list archives
Re: libpcap and select problem
From: Ying Li <hellbunni () yahoo com>
Date: Tue, 26 Oct 2004 06:52:58 -0700 (PDT)
time out as in retval = 0 OS = redhat 9 I used ethereal to monitor traffic. my server is suppose to send something to the client using raw socket, use select/pselect with pcap to wait for reply or resend last packet if timeout (retval =0). I reset(like putting tv_sec=0;tv_usec=1500; before select) the value of timeval before call to select/pselect each time. Most of the time it works fine, but there are some cases where my server sends 2 packets within 0.0001 seconds of each other, which shouldn't happen. This is when I set timeval.sec =0 and timeval.usec = 1500 The other weird thing is that the overall transfer time of a bulk of data is 50%+ faster with these timeout problems, as opposed to setting a longer timeout or taking out the select()(i.e. server sends, waits, sends, assuming no packet lost) --- Guy Harris <guy () alum mit edu> wrote:
On Oct 25, 2004, at 1:27 PM, Ying Li wrote:Sometimes select() times out way too fast, like 0.0001 seconds while my timevar is setto0.001 sec."Times out" in the sense that "retval" is 0? On what OS are you doing this? - This is the tcpdump-workers list. Visit https://lists.sandelman.ca/ to unsubscribe.
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Current thread:
- libpcap and select problem Ying Li (Oct 25)
- Re: libpcap and select problem Guy Harris (Oct 25)
- Re: libpcap and select problem Ying Li (Oct 26)
- Re: libpcap and select problem Ying Li (Oct 27)
- Re: libpcap and select problem Ying Li (Oct 26)
- Re: libpcap and select problem Guy Harris (Oct 25)