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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=ceo@triplebit.com
href="mailto:ceo@triplebit.com">ceo@triplebit.com</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> Monday, September 10, 2007 6:13
AM</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> [Winpcap-users] pcap_loop
pointers</DIV>
<DIV><FONT size=2></FONT><BR></DIV>
<DIV><FONT size=2>I think that my question represents also other
users.</FONT></DIV>
<DIV><FONT size=2><FONT size=3>When using the function "pcap_loop" the
system uses the fallowing callback<BR>whenever a packet arrives
-<BR><BR> typedef void(* pcap_handler)(u_char
*user, const struct pcap_pkthdr<BR>*pkt_header, const u_char
*pkt_data)<BR><BR><BR>My questions-<BR><BR>1. I saw that the pointers pkt_data
and pkt_header differ from packet to<BR>packet.<BR>Does that mean that the
data on which they point occupies different area
in<BR>memory?<BR></FONT></FONT></DIV></BLOCKQUOTE>
<DIV><FONT size=2>Yes.</FONT></DIV>
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<DIV><FONT size=2><FONT size=2></FONT></FONT> </DIV>
<DIV><FONT size=2><FONT size=3>2. How do I know if the data pointed by them is
still valid in a certain<BR>moment?<BR></FONT></FONT></DIV></BLOCKQUOTE>
<DIV><FONT size=2><FONT size=3><FONT size=2>Those pointers are valid *only* in
the context of the pcap_handler callback. Packets are reused as soon as the
pcap_handler callback returns.</FONT></FONT></FONT></DIV>
<DIV><FONT size=2><FONT size=3><FONT size=2></FONT></FONT></FONT> </DIV>
<DIV><FONT size=2><FONT size=3><FONT size=2>Have a nice
day</FONT></FONT></FONT></DIV>
<DIV><FONT size=2><FONT size=3><FONT size=2>GV</FONT></FONT></FONT></DIV>
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<DIV><FONT size=2><FONT size=3><FONT size=2></FONT></FONT></FONT> </DIV>
<DIV><FONT size=2><FONT size=3><BR>Regards<BR><BR>I.
Lesher</FONT><BR><BR></DIV></BLOCKQUOTE>
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