COM_Open (Windows CE 3.0 Device Driver Developement)

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This function initializes the serial port driver.

HANDLE COM_Open(
HANDLE
pContext
,
DWORD
AccessCode
,
DWORD
ShareMode
);

Parameters

pContext

Pointer to a handle returned by the COM_Initfunction.

AccessCode

Specifies the access level requested by the caller, such as shared read or read/write.

ShareMode

Specifies the sharing mode that the calling application passed to the CreateFilefunction.

Return Values

Returns a handle representing the serial port.

Remarks

The user calls this function to open the serial device. The HANDLEreturned must be used by the application in all subsequent calls to the serial driver. This function starts the thread that handles the serial events. This function is exported to applications through CreateFile. If an OEM wishes to support the Telephony API (TAPI), and the OEM is writing their own serial port MDD layer, the OEM must ensure that the MDD layer supports multiple COM_Openrequests from applications. The serial port MDD implementations supplied by Microsoft all meet this requirement.

Requirements

Runs on	Versions	Defined in	Include	Link to
Windows CE OS	1.0 and later	Mdd.c

Note This API is part of the complete Windows CE OS package as provided by Microsoft. The functionality of a particular platform is determined by the original equipment manufacturer (OEM) and some devices may not support this API.

See Also

COM_Close

Last updated on Tuesday, July 13, 2004