csu3_am335x/EVSE/GPL/libpcap-1.9.0/pcap_open_dead.3pcap.in

.\" 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_OPEN_DEAD 3PCAP "3 January 2014"
.SH NAME
pcap_open_dead, pcap_open_dead_with_tstamp_precision \- open a fake
pcap_t for compiling filters or opening a capture for output
.SH SYNOPSIS
.nf
.ft B
#include <pcap/pcap.h>
.ft
.LP
.ft B
pcap_t *pcap_open_dead(int linktype, int snaplen);
pcap_t *pcap_open_dead_with_tstamp_precision(int linktype, int snaplen,
    u_int precision);
.ft
.fi
.SH DESCRIPTION
.PP
.B pcap_open_dead()
and
.B pcap_open_dead_with_tstamp_precision()
are used for creating a
.B 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
.BR pcap_dump_open() ,
.BR pcap_dump() ,
and
.B pcap_dump_close()
to write a savefile if there is no
.B pcap_t
that supplies the packets to be written.
.PP
.I linktype
specifies the link-layer type for the
.BR pcap_t .
.PP
.I snaplen
specifies the snapshot length for the
.BR pcap_t .
.PP
When
.BR pcap_open_dead_with_tstamp_precision() ,
is used to create a
.B pcap_t
for use with
.BR pcap_dump_open() ,
.I precision
specifies the time stamp precision for packets;
.B PCAP_TSTAMP_PRECISION_MICRO
should be specified if the packets to be written have time stamps in
seconds and microseconds, and
.B 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
.BR pcap_compile() .
.SH SEE ALSO
pcap(3PCAP), pcap_compile(3PCAP), pcap_dump_open(3PCAP),
\%pcap-linktype(@MAN_MISC_INFO@)