Get the handle to the actual communication medium. For RTU types it will be a normal file pointer, but TCP will be a socket handle. For this reason, it was decided to only return RTU file pointers. An attempt to get the socket handle will return an ENODEV error.
- Returns:
- int Error code.
- Return values:
-
| >0 | Pointer to communications termios struct. |
| -EBADF | No open module. |
| -ENODEV | This is not an RTU type connection. |
