This section documents the _nanomsg_ 1.0 libary compatible functions.

These functions are provided as a transition aid, for application
developers coming to _NNG_ from _libnanomsg_, and are discouraged
from use in new applications.

TIP: While this is discouraged for long term use, as a transition aid
applications may use the value returned by the
xref:nng_socket_id.3.adoc[`nng_socket_id()`] in these functions just like a
socket descriptor (as if the socket were opened via
xref:nn_socket.3compat.adoc[`nn_socket()`]).
This sort of API intermixing should only be used during transition from
the legacy API to the new API.