hdlcdrv(9) on Linux
The text 9aa536ac85d0, as Debian 6.0 (Squeeze), Debian 5.0 (Lenny), Debian 4.0 (Etch), Debian 3.1 (Sarge), Debian 3.0 (Woody), Debian 2.2 (Potato), Debian 2.1 (Slink), Debian 2.0 (Hamm) shipped it.
HDLC amateur (AX.25) packet radio network driver