Serial Ports Monitor ActiveX Control supports the following standard major I/O requests:

FunctionBrief Description
 IRP_MJ_CREATE This request opens a serial device
 IRP_MJ_DEVICE_CONTROL This request is used to manage a serial port. For a description of the device control requests supported by Serial ports, see IOCTRL request overview.
 IRP_MJ_FLUSH_BUFFERS This request flushes the internal write buffer of a serial device
 IRP_MJ_INTERNAL_DEVICE_CONTROL This request sets internal operating modes on a serial device 
 IRP_MJ_PNP This request is used to query devices and to start, stop, and remove devices
 IRP_MJ_POWER This request controls power management
 IRP_MJ_QUERY_INFORMATION This request queries the end-of-file information for a serial device
 IRP_MJ_READ This request transfers data from a serial device to a client
 IRP_MJ_SET_INFORMATION This request sets the end-of-file information on a serial device
 IRP_MJ_SYSTEM_CONTROL This request supports WMI requests
 IRP_MJ_WRITE This request transfers data from a client to a serial device


See also

IOCTRL Request Overview