PCAP_SETDIRECTION(3PCAP) PCAP_SETDIRECTION(3PCAP)

NAME

pcap_setdirection - set the direction for which packets will be
captured

SYNOPSIS

#include <pcap/pcap.h>

int pcap_setdirection(pcap_t *p, pcap_direction_t d);

DESCRIPTION

pcap_setdirection() is used to specify a direction that packets will
be captured. d is one of the constants PCAP_D_IN, PCAP_D_OUT or
PCAP_D_INOUT. PCAP_D_IN will only capture packets received by the
device, PCAP_D_OUT will only capture packets sent by the device and
PCAP_D_INOUT will capture packets received by or sent by the device.
PCAP_D_INOUT is the default setting if this function is not called.

pcap_setdirection() isn't necessarily fully supported on all
platforms; some platforms might return an error for all values, and
some other platforms might not support PCAP_D_OUT.

This operation is not supported if a ``savefile'' is being read.

RETURN VALUE

pcap_setdirection() returns 0 on success, PCAP_ERROR_NOT_ACTIVATED if
called on a capture handle that has been created but not activated,
or PCAP_ERROR on other errors. If PCAP_ERROR is returned,
pcap_geterr(3PCAP) or pcap_perror(3PCAP) may be called with p as an
argument to fetch or display the error text.

SEE ALSO

pcap(3PCAP)

5 March 2022 PCAP_SETDIRECTION(3PCAP)