This structure describes the current status of a line device.
At a Glance
| Header file: | Tapi.h |
| Windows CE versions: | 1.0 and later |
Syntax
typedef struct linedevstatus_tag {
DWORD dwTotalSize;
DWORD dwNeededSize;
DWORD dwUsedSize;
DWORD dwNumOpens;
DWORD dwOpenMediaModes;
DWORD dwNumActiveCalls;
DWORD dwNumOnHoldCalls;
DWORD dwNumOnHoldPendCalls;
DWORD dwLineFeatures;
DWORD dwNumCallCompletions;
DWORD dwRingMode;
DWORD dwSignalLevel;
DWORD dwBatteryLevel;
DWORD dwRoamMode;
DWORD dwDevStatusFlags;
DWORD dwTerminalModesSize;
DWORD dwTerminalModesOffset;
DWORD dwDevSpecificSize;
DWORD dwDevSpecificOffset;
} LINEDEVSTATUS, FAR *LPLINEDEVSTATUS;
Members
dwTotalSize
Specifies the total size in bytes allocated to this data structure.
dwNeededSize
Specifies the size, in bytes, for this data structure that is needed to hold all the returned data.
dwUsedSize
Specifies the size, in bytes, of the portion of this data structure that contains useful data.
dwNumOpens
Specifies the number of active opens on the line device.
dwOpenMediaModes
Specifies a bit array that indicates for which media modes the line device is currently open.
dwNumActiveCalls
Specifies the number of calls on the line in call states other idle, onhold, onholdpendingtransfer, and onholdpendingconference.
dwNumOnHoldCalls
Specifies the number of calls on the line in the onhold state.
dwNumOnHoldPendCalls
Specifies the number of calls on the line in the onholdpendingtransfer or onholdpendingconference state.
dwLineFeatures
Specifies the line-related API functions that are currently available on this line. It uses the following LINEFEATURE_* constants:
| Value | Description |
| LINEFEATURE_DEVSPECIFIC | Device-specific operations can be used on the line. |
| LINEFEATURE_DEVSPECIFICFEAT | Device-specific features can be used on the line. |
| LINEFEATURE_FORWARD | Forwarding of all addresses can be used on the line. |
| LINEFEATURE_MAKECALL | An outgoing call can be placed on this line using an unspecified address. |
| LINEFEATURE_SETMEDIACONTROL | Media control can be set on this line. |
| LINEFEATURE_SETTERMINAL | Terminal modes for this line can be set. |
dwNumCallCompletions
Specifies the number of outstanding call completion requests on the line.
dwRingMode
Specifies the current ring mode on the line device.
dwSignalLevel
Specifies the current signal level of the connection on the line. This is a value in the range 0x00000000 (weakest signal) to 0x0000FFFF (strongest signal).
dwBatteryLevel
Specifies the current battery level of the line device hardware. This is a value in the range 0x00000000 (battery empty) to 0x0000FFFF (battery full).
dwRoamMode
Specifies the current roam mode of the line device. It uses the following LINEROAMMODE_ constants:
| Value | Description |
| LINEROAMMODE_UNKNOWN | The roam mode is currently unknown, but may be identified later. |
| LINEROAMMODE_UNAVAIL | The roam mode is unavailable and cannot be known. |
| LINEROAMMODE_HOME | The line is connected to the home network node. |
| LINEROAMMODE_ROAMA | The line is connected to the Roam-A carrier and calls are charged accordingly. |
| LINEROAMMODE_ROAMB | The line is connected to the Roam-B carrier and calls are charged accordingly. |
dwDevStatusFlags
Specifies the size, in bytes, of this data structure that contains useful data, of type LINEDEVSTATUSFLAGS_.
| Value | Description |
| LINEDEVSTATUSFLAGS_CONNECTED | Specifies if the line is connected to TAPI. If TRUE, the line is connected and API is able to operate on the line device. If FALSE, the line is disconnected and the application is unable to control the line device using TAPI. |
| LINEDEVSTATUSFLAGS_LOCKED | This bit is most often used with line devices associated with cellular phones. Many cellular phones have a security mechanism that requires the entry of a password to enable the phone to place calls. This bit may be used to indicate to applications that the phone is locked and cannot place calls until the password is entered on the user interface of the phone, so that the application can present an appropriate alert to the user. |
| LINEDEVSTATUSFLAGS_MSGWAIT | This member indicates if the line has a message waiting. If TRUE, a message is waiting; if FALSE, no message is waiting. |
| LINEDEVSTATUSFLAGS_INSERVICE | This member indicates if the line is in service. If TRUE, the line is in service; if FALSE, the line is out of service. |
dwTerminalModesSize
dwTerminalModesOffset
Specify the size, in bytes, of the variably sized device field that contains an array with DWORD-sized entries, and the offset, in bytes, from the beginning of this data structure. This array is indexed by terminal identifiers, in the range from zero to dwNumTerminals minus one. Each entry in the array specifies the current terminal modes for the corresponding terminal set using the lineSetTerminal function for this line. It uses the following LINETERMMODE_ constants:
| Value | Description |
| LINETERMMODE_LAMPS | Lamp events sent from the line to the terminal. |
| LINETERMMODE_BUTTONS | Button-press events sent from the terminal to the line. |
| LINETERMMODE_DISPLAY | Display data sent from the line to the terminal. |
| LINETERMMODE_RINGER | Ringer-control data sent from the switch to the terminal. |
| LINETERMMODE_HOOKSWITCH | Hookswitch events sent between the terminal and the line. |
| LINETERMMODE_MEDIATOLINE | The unidirectional media stream from the terminal to the line associated with a call on the line. Use this value when the routing of both unidirectional channels of a call’s media stream can be controlled independently. |
| LINETERMMODE_MEDIAFROMTERM | The unidirectional media stream from the line to the terminal associated with a call on the line. Use this value when the routing of both unidirectional channels of a call’s media stream can be controlled independently. |
| LINETERMMODE_MEDIABIDIRECT | The bidirectional media stream associated with a call on the line and the terminal. Use this value when the routing of both unidirectional channels of a call’s media stream cannot be controlled independently. |
dwDevSpecificSize
dwDevSpecificOffset
Specify the size, in bytes, of the variably sized device-specific field, and the offset, in bytes, from the beginning of this data structure.
Remarks
Device-specific extensions should use the DevSpecific (dwDevSpecificSize and dwDevSpecificOffset) variably sized area of this data structure.
The members dwAvailableMediaModes through dwAppInfoOffset are available only to applications that open the line device with an API version of 2.0 or later.