Performs the same as ctTagWrite, but with an additional new argument. Writes to the given CitectSCADA I/O Device variable tag. The value, quality and timestamp, not only a value, is converted into the correct data type, then scaled and then written to the tag. If writing to an array element only a single element of the array is written to. This function will generate a write request to the I/O Server. The time taken to complete this function will be dependent on the performance of the I/O Device.
If the value of pctOverlapped is NULL, the function behaves the same as ctTagWrite, and the calling thread is blocked until the write is completed. If the value of pctOverlapped is not NULL, the write is completed asynchronously and the calling thread is not blocked.
ctTagWriteEx(hCTAPI, sTag, sValue, pctOverlapped)
Description: The handle to the CTAPI as returned from ctOpen().
Description: The tag name or tag name and element name, separated by a dot to write to. If the element name is not specified, it will be resolved at runtime as for an unqualified tag reference. You may use the array syntax  to select an element of an array.
Description: The value to write to the tag as a string.
Description: Passes in an overlapped structure so ctTagWriteEx can complete asynchronously. If the pctOverlapped structure is NULL, the function will block, completing synchronously.
TRUE if successful, otherwise FALSE. Use GetLastError() to get extended error information.