BlueZ hci_* API to make the host discoverable

Environment:

• Linux
• BlueZ Bluetooth stack
• C API
• No usage of the dbus interface

I must say that the HCI BlueZ C API ( hci_lib.h ) is poorly documented, having that said, Is there a C hci_* API controlling the host discover-able state? something similar to "hci_write_simple_pairing_mode" enabling control of discoverability?