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<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>Hi Prashanth.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>Till now I worked on IPV4 and TCP. What I
found it works fine. I think for <st1:City w:st="on"><st1:place w:st="on">ur</st1:place></st1:City>
case there might be two reasons.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
<ol style='margin-top:0in' start=1 type=1>
<li class=MsoNormal style='color:navy;mso-list:l0 level1 lfo1'><font size=2
color=navy face=Arial><span style='font-size:10.0pt;font-family:Arial'>you
might fetching the wrong thing for the data. Do one thing check thoroughly
that u r bypassing the UDP header propelr or not. Just be aware that u r
not doing anything wrong in the data bytes calculation of UDP header.<o:p></o:p></span></font></li>
<li class=MsoNormal style='color:navy;mso-list:l0 level1 lfo1'><font size=2
color=navy face=Arial><span style='font-size:10.0pt;font-family:Arial'>It
might be possible that from which pcap file you are reading that packets
may not contain any data. So do one thing open that file in ethereal and
there u can check whether those packets have any data or not.<o:p></o:p></span></font></li>
</ol>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>If these two cant solve <st1:City w:st="on"><st1:place
w:st="on">ur</st1:place></st1:City> problem then let me know. I will try
recheck myself for UDP in my set up.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>Regards<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>Umesh<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
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<p class=MsoNormal><b><font size=2 face=Tahoma><span style='font-size:10.0pt;
font-family:Tahoma;font-weight:bold'>From:</span></font></b><font size=2
face=Tahoma><span style='font-size:10.0pt;font-family:Tahoma'>
winpcap-users-bounces@winpcap.org [mailto:winpcap-users-bounces@winpcap.org] <b><span
style='font-weight:bold'>On Behalf Of </span></b>Prashant Kasal<br>
<b><span style='font-weight:bold'>Sent:</span></b> Saturday, September 22, 2007
12:02 AM<br>
<b><span style='font-weight:bold'>To:</span></b> <st1:PersonName w:st="on">winpcap-users@winpcap.org</st1:PersonName><br>
<b><span style='font-weight:bold'>Subject:</span></b> [Winpcap-users] Retriving
the data from UDP packet</span></font><o:p></o:p></p>
</div>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'><o:p> </o:p></span></font></p>
<div>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'>Hi All,<o:p></o:p></span></font></p>
</div>
<div>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'> I was wondering could anybody help
me out to solve my issue as I'm new to networking programming using WinPcap. My
task is to retrieve the IPv4 header information and UDP header information and
also data of the UDP packet. I'm using WinPCap library for doing the above
task, fortunately I found a sample code in WinPcap site regarding this problem(
<a href="http://www.winpcap.org/docs/docs_41b/html/group__wpcap__tut4.html"
target="_blank">http://www.winpcap.org/docs/docs_41b/html/group__wpcap__tut4.html</a>)
but the code outputs only the header information of both UDP and IPv4
address, along with these info I need data also. When I debugged the
code I came across pcap_next_ex() API where I am supposed to get packet
data also, but it returns empty string. <o:p></o:p></span></font></p>
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<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'> <o:p></o:p></span></font></p>
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<div>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'>Any help would be greatly appreciated. <o:p></o:p></span></font></p>
</div>
<div>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'>-- <br>
Thanks & Regds<br>
Prashanth Kasal <br>
<o:p></o:p></span></font></p>
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