PCAP_ACTIVATE(3)       FreeBSD Library Functions Manual       PCAP_ACTIVATE(3)

NAME

     pcap_activate - 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, a non-zero
     positive value on success with warnings, and a negative value on error.
     A non-zero return value indicates what warning or error condition
     occurred.

     The possible warning values are:

     PCAP_WARNING_PROMISC_NOTSUP
            Promiscuous mode was requested, but the capture source doesn't
            support promiscuous mode.

     PCAP_WARNING_TSTAMP_TYPE_NOTSUP
            The time stamp type specified in a previous
            pcap_set_tstamp_type(3) call isn't supported by the capture source
            (the time stamp type is left as the default),

     PCAP_WARNING
            Another warning condition occurred; pcap_geterr(3) or
            pcap_perror(3) may be called with p as an argument to fetch or
            display a message describing the warning condition.

     The possible error values are:

     PCAP_ERROR_ACTIVATED
            The handle has already been activated.

     PCAP_ERROR_NO_SUCH_DEVICE
            The capture source specified when the handle was created doesn't
            exist.

     PCAP_ERROR_PERM_DENIED
            The process doesn't have permission to open the capture source.

     PCAP_ERROR_PROMISC_PERM_DENIED
            The process has permission to open the capture source but doesn't
            have permission to put it into promiscuous mode.

     PCAP_ERROR_RFMON_NOTSUP
            Monitor mode was specified but the capture source doesn't support
            monitor mode.

     PCAP_ERROR_IFACE_NOT_UP
            The capture source device is not up.

     PCAP_ERROR_CAPTURE_NOTSUP
            Packet capture is not supported on the capture source.

     PCAP_ERROR
            Another error occurred.  pcap_geterr() or pcap_perror() may be
            called with p as an argument to fetch or display a message
            describing the error.

     If PCAP_WARNING_PROMISC_NOTSUP, PCAP_ERROR_NO_SUCH_DEVICE,
     PCAP_ERROR_PERM_DENIED, or PCAP_ERROR_CAPTURE_NOTSUP 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.

     Additional warning and error codes may be added in the future; a program
     should check for positive, negative, and zero return codes, and treat all
     positive return codes as warnings and all negative return codes as
     errors.  pcap_statustostr(3) can be called, with a warning or error code
     as an argument, to fetch a message describing the warning or error code.

     If pcap_activate() fails, the pcap_t * is not closed and freed; it should
     be closed using pcap_close(3).

SEE ALSO

     pcap(3)

                                  3 June 2024                 PCAP_ACTIVATE(3)