NAME

       pcap_dump_open, pcap_dump_fopen - open a file to which to write packets

SYNOPSIS

       #include <pcap/pcap.h>

       pcap_dumper_t *pcap_dump_open(pcap_t *p, const char *fname);
       pcap_dumper_t *pcap_dump_open_append(pcap_t *p, const char *fname);
       pcap_dumper_t *pcap_dump_fopen(pcap_t *p, FILE *fp);

DESCRIPTION

       pcap_dump_open()  is  called to open a ``savefile'' for writing.  fname specifies the name
       of the file to open. The file will have the same format as those used  by  tcpdump(1)  and
       tcpslice(1).  The name "-" is a synonym for stdout.

       pcap_dump_fopen()  is called to write data to an existing open stream fp; this stream will
       be closed by a subsequent call to pcap_dump_close(3PCAP).   Note  that  on  Windows,  that
       stream should be opened in binary mode.

       p  is  a  capture or ``savefile'' handle returned by an earlier call to pcap_create(3PCAP)
       and activated by an earlier call to pcap_activate(3PCAP), or returned by an  earlier  call
       to  pcap_open_offline(3PCAP),  pcap_open_live(3PCAP),  or pcap_open_dead(3PCAP).  The time
       stamp precision, link-layer type, and snapshot length from p are used  as  the  link-layer
       type and snapshot length of the output file.

       pcap_dump_open_append()  is  like pcap_dump_open() but does not create the file if it does
       not exist and, if it does already exist, and is a pcap file with the same  byte  order  as
       the  host opening the file, and has the same time stamp precision, link-layer header type,
       and snapshot length as p, it will write new packets at the end of the file.

RETURN VALUES

       A pointer  to  a  pcap_dumper_t  structure  to  use  in  subsequent  pcap_dump(3PCAP)  and
       pcap_dump_close(3PCAP)  calls  is  returned  on success.  NULL is returned on failure.  If
       NULL is returned, pcap_geterr(3PCAP) can be used to get the error text.

BACKWARD COMPATIBILITY

       The pcap_dump_open_append() function  became  available  in  libpcap  release  1.7.2.   In
       previous releases, there is no support for appending packets to an existing savefile.

SEE ALSO

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

                                          22 August 2018                    PCAP_DUMP_OPEN(3PCAP)