Opens a handle to a communications device.

COMMHANDLE OpenComm(
  LPCSTR lpCommName,        // device name
  DWORD  dwFlags            // action and attributes
);

Parameters

lpCommName

[in] Pointer to a null-terminated string that names the device to be opened. Currently, those devices may be COM1 through COM255.

dwFlags

[in] None defined.

Return Values

A device handle

Success.

INVALID_COMM_HANDLE

Failure. To determine the status, call GetLastRtError.

Status

E_EXIST

COMM channel does not exist.

E_PARAM

Invalid parameter.

Requirements