PCAP_OPEN_DEAD(3PCAP) PCAP_OPEN_DEAD(3PCAP)

NAME

pcap_open_dead, pcap_open_dead_with_tstamp_precision - open a fake
pcap_t for compiling filters or opening a capture for output

SYNOPSIS

#include <pcap/pcap.h>

pcap_t *pcap_open_dead(int linktype, int snaplen);
pcap_t *pcap_open_dead_with_tstamp_precision(int linktype, int snaplen,
u_int precision);

DESCRIPTION

pcap_open_dead() and pcap_open_dead_with_tstamp_precision() are used
for creating a pcap_t structure to use when calling the other
functions in libpcap. It is typically used when just using libpcap
for compiling BPF code; it can also be used if using
pcap_dump_open(3PCAP), pcap_dump(3PCAP), and pcap_dump_close(3PCAP)
to write a savefile if there is no pcap_t that supplies the packets
to be written.

linktype specifies the link-layer type for the pcap_t.

snaplen specifies the snapshot length for the pcap_t.

When pcap_open_dead_with_tstamp_precision(), is used to create a
pcap_t for use with pcap_dump_open(), precision specifies the time
stamp precision for packets; PCAP_TSTAMP_PRECISION_MICRO should be
specified if the packets to be written have time stamps in seconds
and microseconds, and PCAP_TSTAMP_PRECISION_NANO should be specified
if the packets to be written have time stamps in seconds and
nanoseconds. Its value does not affect pcap_compile(3PCAP).

BACKWARD COMPATIBILITY

The pcap_open_dead_with_tstamp_precision() function became available
in libpcap release 1.5.1. In previous releases, there was no
mechanism to open a savefile for writing with time stamps given in
seconds and nanoseconds.

SEE ALSO

pcap(3PCAP), pcap-linktype(5)

3 January 2014 PCAP_OPEN_DEAD(3PCAP)