To help with shutdown of multi-threaded programs nanomsg provides the nn_term() function which closes all open sockets, and releases all related resources.
If a socket is blocked inside a blocking function, such as nn_recv(3), it will be unblocked and EBADF error will be returned to the user. Subsequent calls on such sockets will also return EBADF.
Attempting to open a new socket with nn_socket(3) will result in an ETERM error.
s = nn_socket (AF_SP, NN_PAIR); nn_term (); rc = nn_send (s, "ABC", 3, 0); assert (rc == -1 && errno == EBADF);