Net::Pcap does not work

arc_of_descent has asked for the wisdom of the Perl Monks concerning the following question:

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Re: Net::Pcap does not work by rob_au (Abbot) on Jul 24, 2002 at 11:19 UTC
The `04-loop.t` test script for Net::Pcap can take a moment or two to complete - This script creates a Net::Pcap object which, using the `loop` method, listens for ten packets on the network interface returned by `lookupdev` method of this module and the underlying libpcap library. If your network is nascent, this process may take some time - It may be worthwhile to start an FTP download or alike in the background to generate the necessary network traffic for the `loop` method and underlying libpcap library to capture. The `loop` method of the Net::Pcap library is described in my tutorial on this module here.	[reply] [d/l] [select]
Re: Re: Net::Pcap does not work by arc_of_descent (Hermit) on Jul 24, 2002 at 11:36 UTC
Hi, Thanx for the link to the tutorial I had a brief look at it and will study it further. But unfortunately, the loop method does not work even after i started some heavy downloads, etc Is there something wrong with my libpcap installation? Does tcpdump use libpcap? cause my tcpdump works fine -- arc_of_descent	[reply]
Re: Re: Re: Net::Pcap does not work by lhoward (Vicar) on Jul 24, 2002 at 12:20 UTC
Yes, libpcap is underneath tcpdump as well as being the basis for Net::Pcap. Could it be that your interface is not in promiscuious mode? Newer versions of tcpdump do not put the interface into permiscuous mode by default, if this behavior is inherited from libpcap, you may have to manually put the interace into permiscuous mode. Also make sure you're explicitly telling Net::Pcap which interface you want it to listen to. Permissions can also be a problem with pcap, in many cases the program using it has to run with root permissions.	[reply]
Re: Re: Re: Re: Net::Pcap does not work by arc_of_descent (Hermit) on Jul 24, 2002 at 12:54 UTC
Re: Net::Pcap does not work by arc_of_descent (Hermit) on Jul 24, 2002 at 13:11 UTC
HI Well i just found the problem I installed Net::Pcap on a machine with libpcap version 0.6 and it works great! I have version 0.4 Looks like i have to upgrade my libpcap Is this quirk(?) documented? -- arc_of_descent	[reply]


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