#77 bvlc_send_result and bvlc_send_pdu do not set errno to indicate the error

[Duffy O'Craven]

In h_bbmd.c, routines static int bvlc_send_result(BACNET_IP_ADDRESS*dest_addr, uint16_t result_code) and int bvlc_send_pdu(... state in comments:

• Otherwise, -1 shall be returned and errno set to indicate the error.

but nothing there assigns errno. Its callers such as in
in .//bacnet-stack/src/bacnet/basic/service/s_whois.c if (bytes_sent <= 0)

fprintf(
stderr, "Failed to Send Who-Is Request (%s)!\n", strerror(errno));

print an irrelevant string.