| JP Abgrall | 511eca3 | 2014-02-12 13:46:45 -0800 | [diff] [blame] | 1 | .\" Copyright (c) 1994, 1996, 1997 |
| 2 | .\" The Regents of the University of California. All rights reserved. |
| 3 | .\" |
| 4 | .\" Redistribution and use in source and binary forms, with or without |
| 5 | .\" modification, are permitted provided that: (1) source code distributions |
| 6 | .\" retain the above copyright notice and this paragraph in its entirety, (2) |
| 7 | .\" distributions including binary code include the above copyright notice and |
| 8 | .\" this paragraph in its entirety in the documentation or other materials |
| 9 | .\" provided with the distribution, and (3) all advertising materials mentioning |
| 10 | .\" features or use of this software display the following acknowledgement: |
| 11 | .\" ``This product includes software developed by the University of California, |
| 12 | .\" Lawrence Berkeley Laboratory and its contributors.'' Neither the name of |
| 13 | .\" the University nor the names of its contributors may be used to endorse |
| 14 | .\" or promote products derived from this software without specific prior |
| 15 | .\" written permission. |
| 16 | .\" THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED |
| 17 | .\" WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF |
| 18 | .\" MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. |
| 19 | .\" |
| Haibo Huang | 165065a | 2018-07-23 17:26:52 -0700 | [diff] [blame] | 20 | .TH PCAP_OPEN_LIVE 3PCAP "6 December 2017" |
| JP Abgrall | 511eca3 | 2014-02-12 13:46:45 -0800 | [diff] [blame] | 21 | .SH NAME |
| 22 | pcap_open_live \- open a device for capturing |
| 23 | .SH SYNOPSIS |
| 24 | .nf |
| 25 | .ft B |
| 26 | #include <pcap/pcap.h> |
| 27 | .ft |
| 28 | .LP |
| 29 | .nf |
| 30 | .ft B |
| 31 | char errbuf[PCAP_ERRBUF_SIZE]; |
| 32 | .ft |
| 33 | .LP |
| 34 | .ft B |
| 35 | pcap_t *pcap_open_live(const char *device, int snaplen, |
| 36 | .ti +8 |
| 37 | int promisc, int to_ms, char *errbuf); |
| 38 | .ft |
| 39 | .fi |
| 40 | .SH DESCRIPTION |
| 41 | .B pcap_open_live() |
| 42 | is used to obtain a packet capture handle to look |
| 43 | at packets on the network. |
| 44 | .I device |
| 45 | is a string that specifies the network device to open; on Linux systems |
| 46 | with 2.2 or later kernels, a |
| 47 | .I device |
| 48 | argument of "any" or |
| 49 | .B NULL |
| 50 | can be used to capture packets from all interfaces. |
| 51 | .PP |
| 52 | .I snaplen |
| 53 | specifies the snapshot length to be set on the handle. |
| 54 | .PP |
| 55 | .I promisc |
| 56 | specifies if the interface is to be put into promiscuous mode. |
| 57 | .PP |
| 58 | .I to_ms |
| Haibo Huang | 165065a | 2018-07-23 17:26:52 -0700 | [diff] [blame] | 59 | specifies the packet buffer timeout, as a non-negative value, in |
| 60 | milliseconds. (See |
| 61 | .BR pcap (3PCAP) |
| 62 | for an explanation of the packet buffer timeout.) |
| JP Abgrall | 511eca3 | 2014-02-12 13:46:45 -0800 | [diff] [blame] | 63 | .SH RETURN VALUE |
| 64 | .B pcap_open_live() |
| 65 | returns a |
| 66 | .I pcap_t * |
| 67 | on success and |
| 68 | .B NULL |
| 69 | on failure. |
| 70 | If |
| 71 | .B NULL |
| 72 | is returned, |
| 73 | .I errbuf |
| 74 | is filled in with an appropriate error message. |
| 75 | .I errbuf |
| 76 | may also be set to warning text when |
| 77 | .B pcap_open_live() |
| 78 | succeeds; to detect this case the caller should store a zero-length string in |
| 79 | .I errbuf |
| 80 | before calling |
| 81 | .B pcap_open_live() |
| 82 | and display the warning to the user if |
| 83 | .I errbuf |
| 84 | is no longer a zero-length string. |
| 85 | .I errbuf |
| 86 | is assumed to be able to hold at least |
| 87 | .B PCAP_ERRBUF_SIZE |
| 88 | chars. |
| 89 | .SH SEE ALSO |
| 90 | pcap(3PCAP), pcap_create(3PCAP), pcap_activate(3PCAP) |