pcap_setnonblock, pcap_getnonblock - set or get the state of non-block- ing mode on a capture device
#include <pcap/pcap.h> char errbuf[PCAP_ERRBUF_SIZE]; pcap_setnonblock(3) *p, int nonblock, char *errbuf); int pcap_getnonblock(pcap_t *p, char *errbuf);
pcap_setnonblock(3) puts a capture handle into ``non-blocking'' mode, or takes it out of ``non-blocking'' mode, depending on whether the non- block argument is non-zero or zero. It has no effect on ``savefiles''. If there is an error, -1 is returned and errbuf is filled in with an appropriate error message; otherwise, 0 is returned. In ``non-block- ing'' mode, an attempt to read from the capture descriptor with pcap_dispatch() will, if no packets are currently available to be read, return 0 immediately rather than blocking waiting for packets to arrive. pcap_loop() and pcap_next() will not work in ``non-blocking'' mode. When first activated with pcap_activate() or opened with pcap_open_live() , a capture handle is not in ``non-blocking mode''; a call to pcap_setnonblock(3) is required in order to put it into ``non- blocking'' mode.
pcap_getnonblock() returns the current ``non-blocking'' state of the capture descriptor; it always returns 0 on ``savefiles''. If there is an error, -1 is returned and errbuf is filled in with an appropriate error message. errbuf is assumed to be able to hold at least PCAP_ERRBUF_SIZE chars.
pcap(3), pcap_loop(3), pcap_next_ex(3), pcap_geterr(3) 5 April 2008 pcap_setnonblock(3)
libpcap 1.7.2 - Generated Sat Mar 14 15:47:06 CDT 2015