INT 14 - TelAPI - "telportosn" - GET SESSION NUMBER FOR COM PORT AH = E9h DX = serial port number (0000h-0003h = COM1-COM4) Return: AX >= 0000h session number AX < 0000h error code (see #00397) SeeAlso: AH=E0h,AH=E8h,AH=EAh,AX=FF00h