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PCAP_COMPILE(3)		   Library Functions Manual	       PCAP_COMPILE(3)

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(@MAN_MISC_INFO@)	for the	syntax of that	string.	  pro-
       gram is a pointer to a bpf_program struct and is	filled in by pcap_com-
       pile().	optimize controls whether optimization on the  resulting  code
       is  performed.	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_NETMASK_UN-
       KNOWN  can be supplied; tests for IPv4 broadcast	addresses will fail to
       compile,	but all	other tests in the filter program will be OK.

       NOTE: in	libpcap	1.8.0 and later, pcap_compile()	can be used in	multi-
       ple  threads  within a single process.  However,	in earlier versions of
       libpcap,	it is not safe to use pcap_compile() in	multiple threads in  a
       single  process without some form of mutual exclusion allowing only one
       thread to call it at any	given time.

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

SEE ALSO
       pcap(3),	pcap_setfilter(3), pcap_freecode(3), pcap_geterr(3), pcap-fil-
       ter(@MAN_MISC_INFO@)

				 7 April 2014		       PCAP_COMPILE(3)

NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | SEE ALSO

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