const syscall.IP_ADD_MEMBERSHIP

2 uses

	syscall (current package)
		zerrors_darwin_arm64.go#L551: 	IP_ADD_MEMBERSHIP                 = 0xc

	net
		sockoptip_posix.go#L19: 	err := fd.pfd.SetsockoptIPMreq(syscall.IPPROTO_IP, syscall.IP_ADD_MEMBERSHIP, mreq)