Dialogic 6.2 - Manual (Page 28)

The Bfv API Functions
November 2009 28
The BTLINE Structure
When an application calls the BfvLineAttach (or
BfvSessionAttach) function to open and attach a specified channel,
the function creates a separate BTLINE structure for a channel and
returns a pointer to the line structure. All information about the
channel is stored in its BTLINE structure, but only the line state,
the line type, and channel number are actually relevant. The
BfvLineDetach (or BfvSessionDetach) function deallocates a
BTLINE structure.
Applications do not directly access the internal fields of the BTLINE
structure, but instead use functions, described in detail in the
Bfv API Reference Manual, and the following macros, described in
detail with other macros in the Bfv API Reference Manual:
LINE_HAS_CAP(
lp, cap)
Confirms whether or not the line has the specified capability cap.
LINE_STATE(
lp)
Returns or sets the line state of the specified line.
LINE_TYPE(
lp)
Returns the line type of the specified line.
LINE_UNIT_NUM(
lp)
Returns the channel number of the specified line.
A line is always in one of the following states:
LINE_STATE_AWAIT_TRAINING
LINE_STATE_CONNECTED
LINE_STATE_FAX_MODE
LINE_STATE_HOLDUP
LINE_STATE_IDLE
LINE_STATE_NOLOOP
LINE_STATE_OFF_HOOK
LINE_STATE_RCV_INFO
LINE_STATE_RESETTING
LINE_STATE_RETAIN
LINE_STATE_RINGING
LINE_STATE_TURNAROUND