INT 2F C - MS Windows - VIRTUAL DEVICE CALL OUT API(Application Program[ming] Interface) The defined set of calls which a program may make to interact with or request services of the operating system or environment under which it is running. Because the inputs and outputs of the calls are well-defined, a program using the API can continue using the identical calls even if the internal organization of the program providing the API changes. AX = 1607h BX = virtual device ID (see #02642) CX = (usually) callout subfunction Return: (usually) AX,BX,CX,DX,ES contain results Notes: more of a convention than an API(Application Program[ming] Interface) The defined set of calls which a program may make to interact with or request services of the operating system or environment under which it is running. Because the inputs and outputs of the calls are well-defined, a program using the API can continue using the identical calls even if the internal organization of the program providing the API changes., this call specifies a standard mechanism for Windows enhanced-mode virtual devices (VxDA virtual device driver for Windows 3.x or 95. So called because nearly all of the Windows 3.0 drivers had names of the form "VdeviceD". See also device driver.'s) to talk to DOS device drivers and TSRs see below for details on several virtual devices SeeAlso: AX=1605h,AX=1607h/BX=000Ch,AX=1607h/BX=0014h,AX=1607h/BX=0015h SeeAlso: AX=1607h/BX=0018h,AX=1684h"DEVICE API(Application Program[ming] Interface) The defined set of calls which a program may make to interact with or request services of the operating system or environment under which it is running. Because the inputs and outputs of the calls are well-defined, a program using the API can continue using the identical calls even if the internal organization of the program providing the API changes.",AX=C020h