|
include vcd.inc VxDcall VCD_Get_Focus |
The VCD_Get_Focus service returns the virtual machine handle of the current owner of a COM port. Focus can be set with a Set_Device_Focus control message sent using the System_Control service, and specifying the VCD device.
EAX
Specifies the hardware COM port number. It must be in the range 1 to 4.
If the carry flag is clear, the EBX register contains virtual machine handle or zero if there is no owner.
The carry flag is set if the port is not available.
EBX, Flags