| .\" @(#) $Header: /tcpdump/master/libpcap/pcap_compile.3pcap.in,v 1.1 2008-10-21 07:33:02 guy Exp $ |
| .\" |
| .\" Copyright (c) 1994, 1996, 1997 |
| .\" The Regents of the University of California. All rights reserved. |
| .\" |
| .\" Redistribution and use in source and binary forms, with or without |
| .\" modification, are permitted provided that: (1) source code distributions |
| .\" retain the above copyright notice and this paragraph in its entirety, (2) |
| .\" distributions including binary code include the above copyright notice and |
| .\" this paragraph in its entirety in the documentation or other materials |
| .\" provided with the distribution, and (3) all advertising materials mentioning |
| .\" features or use of this software display the following acknowledgement: |
| .\" ``This product includes software developed by the University of California, |
| .\" Lawrence Berkeley Laboratory and its contributors.'' Neither the name of |
| .\" the University nor the names of its contributors may be used to endorse |
| .\" or promote products derived from this software without specific prior |
| .\" written permission. |
| .\" THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED |
| .\" WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF |
| .\" MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. |
| .\" |
| .TH PCAP_COMPILE 3PCAP "5 April 2008" |
| .SH NAME |
| pcap_compile \- compile a filter expression |
| .SH SYNOPSIS |
| .nf |
| .ft B |
| #include <pcap/pcap.h> |
| .ft |
| .LP |
| .ft B |
| int pcap_compile(pcap_t *p, struct bpf_program *fp, |
| .ti +8 |
| const char *str, int optimize, bpf_u_int32 netmask); |
| .ft |
| .fi |
| .SH DESCRIPTION |
| .B pcap_compile() |
| is used to compile the string |
| .I str |
| into a filter program. See |
| .BR pcap-filter (@MAN_MISC_INFO@) |
| for the syntax of that string. |
| .I program |
| is a pointer to a |
| .I bpf_program |
| struct and is filled in by |
| .BR pcap_compile() . |
| .I optimize |
| controls whether optimization on the resulting code is performed. |
| .I 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_UNKNOWN can be supplied; tests |
| for IPv4 broadcast addresses will fail to compile, but all other tests in |
| the filter program will be OK. |
| .SH RETURN VALUE |
| .B pcap_compile() |
| returns 0 on success and \-1 on failure. |
| If \-1 is returned, |
| .B pcap_geterr() |
| or |
| .B pcap_perror() |
| may be called with |
| .I p |
| as an argument to fetch or display the error text. |
| .SH SEE ALSO |
| pcap(3PCAP), pcap_setfilter(3PCAP), pcap_freecode(3PCAP), |
| pcap_geterr(3PCAP), pcap-filter(@MAN_MISC_INFO@) |