NAME

       pcap_set_protocol_linux - set capture protocol for a not-yet-activated capture handle

SYNOPSIS

       #include <pcap/pcap.h>

       int pcap_set_protocol_linux(pcap_t *p, int protocol);

DESCRIPTION

       On  network  interface devices on Linux, pcap_set_protocol_linux() sets the protocol to be
       used in the socket(2) call to create a capture socket when the handle is  activated.   The
       argument  is  a  link-layer  protocol  value, such as the values in the <linux/if_ether.h>
       header file, specified in host byte order.  If  protocol  is  non-zero,  packets  of  that
       protocol  will  be  captured  when the handle is activated, otherwise, all packets will be
       captured.  This function is only provided on Linux, and, if it is used on any device other
       than a network interface, it will have no effect.

       It  should  not  be  used  in  portable  code;  instead, a filter should be specified with
       pcap_setfilter(3PCAP).

       If a given network interface provides a standard link-layer header, with a standard packet
       type,  but provides some packet types with a different socket-layer protocol type from the
       one in the link-layer header, that packet type cannot be filtered with a filter  specified
       with  pcap_setfilter()  but  can  be filtered by specifying the socket-layer protocol type
       using pcap_set_protocol_linux().

RETURN VALUE

       pcap_set_protocol_linux() returns 0 on success or  PCAP_ERROR_ACTIVATED  if  called  on  a
       capture handle that has been activated.

BACKWARD COMPATIBILITY

       This function became available in libpcap release 1.9.0.

SEE ALSO

       pcap(3PCAP), pcap_create(3PCAP), pcap_activate(3PCAP)

                                          22 August 2018           PCAP_SET_PROTOCOL_LINUX(3PCAP)