Technical data

isdnio(7I) Ioctl Requests SunOS 5.5
Auxiliary channels
Auxiliary channelsare non-ISDN hardware interfaces that are closely
tied to the ISDN interfaces. An example would be a video or audio
coder/decoder (codec). The existence of an auxiliary channel usually
implies that one or more B-channels can be “connected” to an auxiliary
interface in hardware.
Management pseudo-channels
A management pseudo-channelis used for the management of a con-
troller, interface, or hardware channel. Management channels allow for
out-of-band control of hardware interfaces and for out-of-band
notification of status changes. There is at least one managementdevice
per hardware interface.
There are three different types of management channels implemented by
ISDN hardware drivers:
A controller management device handlesall ioctls that simultane-
ously affect hardware channels on different interfaces. Examples
include resetting a controller, µ-code downloading of a controller, or
the connection of an ISDN B-channelto an auxiliary channel that
represents an audio coder/decoder (codec). The latter case would be
accomplished using theISDN_SET_CHANNEL ioctl.
An interface management device handles all ioctls that affect multi-
ple channels on the same interface. Messages associated with the
activation and deactivation of an interface arrive on the management
device associated with the D channelof an ISDN interface.
Auxiliary interfaces may also have management devices. See the
hardware specific man pages for operations on auxiliary devices.
Trace pseudo-channels
A device driver may choose to implement a trace device for a data or
management channel.Trace channels receive a specialM_PROTO header
with the original channel’s originalM_PROTO or M_DATA message
appended to the special header. The header is described by:
typedef struct {
uint_t seq; /∗ Sequence number ∗/
int type; /∗ device dependent ∗/
struct timeval timestamp;
char _f[8]; /∗ filler ∗/
} audtrace_hdr_t;
ISDN Channel types
The isdn_chan_t type enumerates the channelsavailable onISDN interfaces. If a particu-
lar controller implements any auxiliary channels then those auxiliary channels will be
described in a controller specific manual page. The defined channelsare described by the
isdn_chan_t type as shown below:
/∗ ISDN channels ∗/
typedef enum {
ISDN_CHAN_NONE = 0x0, /∗ No channel given ∗/
ISDN_CHAN_SELF, /∗ The channel performing the ioctl ∗/
7I-154 modified 7 Apr 1994