local IP address
local port or 0 to use the wildcard "any" port
0 on success or -1 on failure. On failure errno is set appropriately.
Errors: as the overridden method but also sets errno to EINVAL if the address does not contain a valid IP address string.
Assigns a local address and optionally a port to this socket and memorises address and port. This socket needs to have been created by socket().