Windows Mobile 6.5
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This function enables the application to set the configuration of a media-stream device on a line device to a setup previously obtained using the lineGetDevConfig or lineConfigDialogEdit function. For example, the contents of this structure could specify data rate, character format, modulation schemes, and error control protocol settings for a datamodem media device associated with the line.

LONG lineSetDevConfig(
  DWORD dwDeviceID, 
  LPVOID const lpDeviceConfig, 
  DWORD dwSize, 
  LPCTSTR lpszDeviceClass


[in] Line device to be configured.


[in] Pointer to the opaque configuration data structure that was returned by the lineGetDevConfig function in the variable portion of the VARSTRING structure.


[in] Number of bytes in the structure pointed to by lpDeviceConfig. This value is returned in the dwStringSize member in the VARSTRING structure returned by lineGetDevConfig.


[in] Pointer to a null-terminated string that specifies the device class of the device whose configuration is to be set. Valid device class strings are the same as those specified for the lineGetID function.

Zero indicates success. A negative error number indicates that an error occurred. The following table shows the return values for this function.

Value Description


The device id is incorrect.


The device class is invalid.


The line state is invalid.


The parameter is invalid.


The pointer is invalid.


The driver was not found.


The device was not found.


Not enough memory is available.


The operation failed.


The operation is unavailable.


The resource is unavailable.


A parameter was uninitialized.

Typically, an application calls the lineGetID function to identify the media stream device associated with a line, and then calls lineConfigDialogEdit to enable the user to change the device configuration and affect the current call or next call with those changes by passing the output of lineConfigDialogEdit to lineSetDevConfig. When the user wants to call the same destination again, this lineSetDevConfig function can be used to restore the configuration settings selected by the user.

The exact format of the data contained within the structure is specific to the line and media stream API (device class), is undocumented, and is undefined. The application must treat it as opaque and not manipulate the contents directly. Generally, the structure can be sent using this function only to the same device from which it was obtained. Certain telephony service providers may, however, permit structures to be interchanged between identical devices (that is, multiple ports on the same multiport modem card). Such interchangeability is not guaranteed in any way, even for devices of the same device class.

Some service providers may permit the configuration to be set while a call is active, and others may not.

The lineSetDevConfig function returns LINEERR_OPERATIONFAILED if the protocol type, data compression and header compression values in CELLGPRSCONNECTIONINFO structure are set CELLDEVCONFIG_GPRSPROTOCOL_UNKNOWN and CELLDEVCONFIG_GPRSCOMPRESSION_UNKNOWN.

Windows Embedded CEWindows CE 1.0 and later
Windows MobileWindows Mobile Version 5.0 and later