PCAP\_CAN\_SET\_RFMON(3PCAP) PCAP\_CAN\_SET\_RFMON(3PCAP) # [NAME](#NAME) pcap\_can\_set\_rfmon - check whether monitor mode can be set for a not-yet-activated capture handle # [SYNOPSIS](#SYNOPSIS) ``` #include ``` ``` int pcap_can_set_rfmon(pcap_t *p); ``` # [DESCRIPTION](#DESCRIPTION) **pcap\_can\_set\_rfmon**() checks whether monitor mode could be set on a capture handle when the handle is activated. # [RETURN VALUE](#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**](#PCAP_ERROR_NO_SUCH_DEVICE) The capture source specified when the handle was created doesn't exist. [**PCAP\_ERROR\_PERM\_DENIED**](#PCAP_ERROR_PERM_DENIED) The process doesn't have permission to check whether monitor mode could be supported. [**PCAP\_ERROR\_ACTIVATED**](#PCAP_ERROR_ACTIVATED) The capture handle has already been activated. [**PCAP\_ERROR**](#PCAP_ERROR) Another error occurred. [**pcap\_geterr**(3PCAP)](/man/os/libpcap/pcap_geterr.3PCAP) or [**pcap\_perror**(3PCAP)](/man/os/libpcap/pcap_perror.3PCAP) 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**(3PCAP)](/man/os/libpcap/pcap_statustostr.3PCAP) can be called, with a warning or error code as an argument, to fetch a message describing the warning or error code. # [SEE ALSO](#SEE_ALSO) [**pcap**(3PCAP)](/man/os/libpcap/pcap.3PCAP), [**pcap\_create**(3PCAP)](/man/os/libpcap/pcap_create.3PCAP), [**pcap\_activate**(3PCAP)](/man/os/libpcap/pcap_activate.3PCAP), [**pcap\_set\_rfmon**(3PCAP)](/man/os/libpcap/pcap_set_rfmon.3PCAP) 31 July 2016 --- Document: pcap_can_set_rfmon(3pcap) from libpcap 1.11.0-r0 (Chainguard OS) Source: https://github.com/the-tcpdump-group/libpcap.git