pcap_offline_filter(3pcap) [linux man page]

PCAP_OFFLINE_FILTER(3PCAP)												PCAP_OFFLINE_FILTER(3PCAP)

NAME

       pcap_offline_filter - check whether a filter matches a packet

SYNOPSIS

       #include <pcap/pcap.h>

       int pcap_offline_filter(struct bpf_program *fp,
	       const struct pcap_pkthdr *h, const u_char *pkt)

DESCRIPTION

       pcap_offline_filter()  checks  whether a filter matches a packet.  fp is a pointer to a bpf_program struct, usually the result of a call to
       pcap_compile().	h points to the pcap_pkthdr structure for the packet, and pkt points to the data in the packet.

RETURN VALUE

       pcap_offline_filter() returns the return value of the filter program.  This will be zero if the packet doesn't match the  filter  and  non-
       zero if the packet matches the filter.

SEE ALSO

       pcap(3PCAP), pcap_compile(3PCAP)

								    13 May 2008 					PCAP_OFFLINE_FILTER(3PCAP)

PCAP_COMPILE(3PCAP)													       PCAP_COMPILE(3PCAP)

NAME

       pcap_compile - compile a filter expression

SYNOPSIS

       #include <pcap/pcap.h>

       int pcap_compile(pcap_t *p, struct bpf_program *fp,
	       const char *str, int optimize, bpf_u_int32 netmask);

DESCRIPTION

       pcap_compile()  is  used  to compile the string str into a filter program.  See pcap-filter(7) for the syntax of that string.  program is a
       pointer to a bpf_program struct and is filled in by pcap_compile().  optimize controls whether optimization on the resulting code  is  per-
       formed.	 netmask  specifies  the  IPv4	netmask of the network on which packets are being captured; it is used only when checking for IPv4
       broadcast addresses in the filter program.  If the netmask of the network on which packets are being captured isn't known to  the  program,
       or  if  packets	are  being  captured  on  the Linux "any" pseudo-interface that can capture on more than one network, a value of PCAP_NET-
       MASK_UNKNOWN can be supplied; tests for IPv4 broadcast addresses will fail to compile, but all other tests in the filter  program  will	be
       OK.

RETURN VALUE

       pcap_compile()  returns 0 on success and -1 on failure.	If -1 is returned, pcap_geterr() or pcap_perror() may be called with p as an argu-
       ment to fetch or display the error text.

SEE ALSO

       pcap(3PCAP), pcap_setfilter(3PCAP), pcap_freecode(3PCAP), pcap_geterr(3PCAP), pcap-filter(7)

								   5 April 2008 					       PCAP_COMPILE(3PCAP)