pcap_activate(3) activate a capture handle

SYNOPSIS

#include <pcap/pcap.h>

int pcap_activate(pcap_t *p);

DESCRIPTION

pcap_activate() is used to activate a packet capture handle to look at packets on the network, with the options that were set on the handle being in effect.

RETURN VALUE

pcap_activate() returns 0 on success without warnings, PCAP_WARNING_PROMISC_NOTSUP on success on a device that doesn't support promiscuous mode if promiscuous mode was requested, PCAP_WARNING_TSTAMP_TYPE_NOTSUP on success if the time stamp type specified in a previous pcap_set_tstamp_type() call isn't supported by the capture source (the time stamp type is left as the default), PCAP_WARNING on success with any other warning, PCAP_ERROR_ACTIVATED if the handle has already been activated, PCAP_ERROR_NO_SUCH_DEVICE if the capture source specified when the handle was created doesn't exist, PCAP_ERROR_PERM_DENIED if the process doesn't have permission to open the capture source, PCAP_ERROR_PROMISC_PERM_DENIED if the process has permission to open the capture source but doesn't have permission to put it into promiscuous mode, PCAP_ERROR_RFMON_NOTSUP if monitor mode was specified but the capture source doesn't support monitor mode, PCAP_ERROR_IFACE_NOT_UP if the capture source is not up, and PCAP_ERROR if another error occurred. If PCAP_WARNING or PCAP_ERROR is returned, pcap_geterr() or pcap_perror() may be called with p as an argument to fetch or display a message describing the warning or error. If PCAP_WARNING_PROMISC_NOTSUP, PCAP_ERROR_NO_SUCH_DEVICE, or PCAP_ERROR_PERM_DENIED is returned, pcap_geterr() or pcap_perror() may be called with p as an argument to fetch or display an message giving additional details about the problem that might be useful for debugging the problem if it's unexpected.