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. The calling thread is blocked until the write is completed. Writing operation will succeed only for those tag elements which have read/write access.
ctTagWrite(hCTAPI, sTag, sValue)
Description: The handle to the CTAPI as returned from ctOpen().
Description: The tag name or tag name and element name, separated by a dot. 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.
TRUE if successful, otherwise FALSE. Use GetLastError() to get extended error information.
ctOpen, ctTagWrite, ctTagRead
HANDLE hCTAPI = ctOpen(NULL, NULL, NULL, 0);ctTagWrite (hCTAPI,"PV123", "123.12"); ctTagWrite (hCTAPI,"PV123.Field", "123.12"); ctTagWrite (hCTAPI,"PV123.Field.V", "123.12"); ctTagWrite (hCTAPI,"PV123.ControlMode", "1"); ctTagWrite (hCTAPI,"PV123.Status", "0");