int l1hold; /* hold layer 1 (1=on, 0=off) */
int l2hold; /* hold layer 2 (1=force, -1=disable, 0=default) */
int gsm; /* interface is an GSM interface */
+ unsigned int ss5; /* set, if SS5 signalling enabled, also holds feature bits */
int channel_force; /* forces channel by protocol */
int nodtmf; /* disables DTMF */
struct select_channel *out_channel; /* list of channels to select */