## 29.12. Library Functions

The `libecpg` library primarily contains “hidden” functions that are used to implement the functionality expressed by the embedded SQL commands. But there are some functions that can usefully be called directly. Note that this makes your code unportable.

- `ECPGdebug(int `on`, , FILE *`stream`)` turns on debug logging if called with the first argument non-zero. Debug logging is done on `stream`. The log contains all SQL statements with all the input variables inserted, and the results from the PostgreSQL server. This can be very useful when searching for errors in your SQL statements.

- `ECPGstatus()` returns true if you are connected to a database and false if not.