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<DIV style="FONT: 10pt arial">----- Original Message ----- </DIV>
<DIV
style="BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: black"><B>From:</B>
<A title=mailinglists+winpcap@oliverzheng.com
href="mailto:mailinglists+winpcap@oliverzheng.com">Oliver Zheng</A> </DIV>
<DIV style="FONT: 10pt arial"><B>To:</B> <A title=winpcap-users@winpcap.org
href="mailto:winpcap-users@winpcap.org">winpcap-users@winpcap.org</A> </DIV>
<DIV style="FONT: 10pt arial"><B>Sent:</B> Wednesday, December 10, 2008 4:38
PM</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> Re: [Winpcap-users] Captured
packets buffered and not returned totheapplication immediately</DIV>
<DIV><BR></DIV>Ah that makes sense. Thanks for the clarification.<BR>
<DIV class=gmail_quote><BR>
<BLOCKQUOTE class=gmail_quote
style="PADDING-LEFT: 1ex; MARGIN: 0pt 0pt 0pt 0.8ex; BORDER-LEFT: rgb(204,204,204) 1px solid">
<DIV bgcolor="#ffffff">
<DIV><FONT size=2>If you set the timeout to 0 (infinite timeout), mintocopy
is the factor affecting the reception.</FONT></DIV></DIV></BLOCKQUOTE>
<DIV> </DIV>
<DIV>Where is mintocopy defined? </DIV>
<DIV> </DIV></DIV></BLOCKQUOTE>
<DIV><FONT size=2>The default value when you open an adapter with
pcap_open/pcap_open_live is 16000 bytes. You can change it with
pcap_setmintocopy(<A
href="http://www.winpcap.org/docs/docs_41b4/html/group__wpcapfunc.html#gb14ceacbf1c2f63026416dd73f80dc0d"><FONT
size=3>http://www.winpcap.org/docs/docs_41b4/html/group__wpcapfunc.html#gb14ceacbf1c2f63026416dd73f80dc0d</FONT></A>).</FONT><BR><BR></DIV>
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<BLOCKQUOTE class=gmail_quote
style="PADDING-LEFT: 1ex; MARGIN: 0pt 0pt 0pt 0.8ex; BORDER-LEFT: rgb(204,204,204) 1px solid">
<DIV bgcolor="#ffffff"></DIV>
<DIV bgcolor="#ffffff"><FONT size=2>pcap_next_ex (or any other WinPcap
receive function) will return</FONT></DIV>
<DIV bgcolor="#ffffff"><FONT size=2>- after the timeout (unless you used
0)</FONT></DIV>
<DIV bgcolor="#ffffff"><FONT size=2>- when at least mintocopy bytes are
stored in the kernel buffer</FONT></DIV>
<DIV bgcolor="#ffffff"><FONT size=2></FONT> </DIV>
<DIV bgcolor="#ffffff"><FONT size=2>(whatever happens first).</FONT></DIV>
<DIV bgcolor="#ffffff"><FONT size=2></FONT> </DIV>
<DIV bgcolor="#ffffff"><FONT size=2>It's not a bug in WinPcap, this is by
design. Why are you using an infinite timeout?</FONT></DIV>
<DIV bgcolor="#ffffff"></DIV></BLOCKQUOTE><FONT size=2></FONT>
<DIV class=gmail_quote><BR>Is that the intended usage, to use a timeout? I
really do not need to have a timeout; I want a packet when it arrives. But if
the only way to circumvent mintocopy is to have a timeout, then I don't mind
it. Then I suppose pcap_next_ex() would be more useful than pcap_next() since
its return code indicates a timeout...<BR></DIV></BLOCKQUOTE>
<DIV><FONT size=2>I definitely suggest you to use pcap_next_ex().</FONT></DIV>
<BLOCKQUOTE
style="PADDING-RIGHT: 0px; PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #000000 2px solid; MARGIN-RIGHT: 0px"><FONT
size=2></FONT><FONT size=2></FONT>
<DIV class=gmail_quote><BR>Is there a way to change the size of mintocopy? I
am guessing no, since that's kernel level code.</DIV>
<DIV class=gmail_quote> </DIV></BLOCKQUOTE>
<DIV><FONT size=2>pcap_setmintocopy().</FONT></DIV><FONT size=2></FONT>
<DIV class=gmail_quote> </DIV>
<DIV class=gmail_quote><FONT size=2>Have a nice day</FONT></DIV>
<DIV class=gmail_quote><FONT size=2>GV</FONT></DIV>
<BLOCKQUOTE
style="PADDING-RIGHT: 0px; PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #000000 2px solid; MARGIN-RIGHT: 0px">
<DIV class=gmail_quote><BR><BR>Cheers,<BR>Oliver<BR></DIV>
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