int mongoc_socket_connect (mongoc_socket_t *sock, const struct sockaddr *addr, socklen_t addrlen, int64_t expire_at);
This function is a wrapper around the BSD socket connect() interface. It provides better portability between UNIX-like and Microsoft Windows platforms.
This function performs a socket connection but will fail if @expire_at has been reached by the monotonic clock. Keep in mind that this is an absolute timeout in milliseconds. You should add your desired timeout to bson_get_monotonic_time().
0 if successful, -1 on failure and errno is set.