Thread: libpcap: How to timeout pcap_loop() ?

I'm using the libpcap library to sniff packets on an interface. (My target OS is Linux, but I don't think that helps here.)

I'm using pcap_loop() to capture packets, but pcap_loop() waits until a packet is captured before returning to the calling function. Is there any way to force it to only listen for a specified amount of time? I'd like to loop the main program while just checking each loop for new packets, rather than having to wait for a new packet to arrive before doing anything. I've looked around and am pretty sure there's no built-in feature for this (that works on Linux) so might there exist some type of work-around?

probably you want to look something in inet like
http://www.tcpdump.org/lists/workers.../msg00178.html

Haven't read it throughoutly but seems to me they are talking about same type of problems

From the link:

If switching to pcap_dispatch() instead of pcap_loop() is not a bad option
for you, one other way of doing what you want is use select for timing
out. So you can access the pcap file descriptor and select on it for
either reads or timeouts. When select returns, if read fd_set is set, you
can call pcap_dispatch(), otherwise for timeout you can do your other
tasks.

What's this "select" he's talking about?

(BTW, sorry for taking so long to return, holidays+travel+start of school kept me busy. :P )