PCAP_CAN_SET_RFMON(3)  FreeBSD Library Functions Manual  PCAP_CAN_SET_RFMON(3)

NAME

     pcap_can_set_rfmon - check whether monitor mode can be set for a not-yet-
     activated capture handle

SYNOPSIS

     #include <pcap/pcap.h>

     int pcap_can_set_rfmon(pcap_t *p);

DESCRIPTION

     pcap_can_set_rfmon() checks whether monitor mode could be set on a
     capture handle when the handle is activated.

RETURN VALUE

     pcap_can_set_rfmon() returns 0 if monitor mode could not be set, 1 if
     monitor mode could be set, and a negative value on error.  A negative
     return value indicates what error condition occurred.  The possible error
     values are:

     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 check whether monitor mode
            could be supported.

     PCAP_ERROR_ACTIVATED
            The capture handle has already been activated.

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

     Additional error codes may be added in the future; a program should check
     for 0, 1, and negative, return codes, and treat 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.

SEE ALSO

     pcap(3), pcap_create(3), pcap_activate(3), pcap_set_rfmon(3)

                                 31 July 2016            PCAP_CAN_SET_RFMON(3)