Virtual Devices (3.1) (vdag31qh.hlp) (Table of Contents; Topic list)
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DOSMGR_Instance_Device
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include dosmgr.inc
 
VxDcall DOSMGR_Instance_Device
 
The DOSMGR_Instance_Device service instances the indicated installed MS-DOS
character device driver.
 
This service is only valid during the Init_Complete message.
 
Parameter  Description
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ESI        Points to the 8-character device name. This name must exactly
           match the name as it found in the device header in low memory.
           Characters must be in uppercase; case conversion is not
           performed. Names shorter than 8 characters must be padded with
           spaces. The colon (:) must not be used.
 
Return Value
 
The carry flag is clear if the device is instanced. Otherwise, the carry
flag is set to indicate one of the following errors:
 
♦  No device with this name in device list
 
♦  Device is in MS-DOS RAM BIOS (Segment of device == 70h)
 
♦  User overides with the GLOBAL setting in SYSTEM.INI
 
Comments
 
This service applies only to installed character devices (device segment not
equal to 70h). It cannot instance devices that are in the MS-DOS RAM BIOS
because there is no way to determine their start and end addresses. It is
the job of the MS-DOS instancing to correctly instance things related to
character devices in the MS-DOS RAM BIOS.
 
This service instances the entire device. It cannot differentiate code and
data.
 
This service is available during the Init_Complete message only and cannot
work until the DOSMGR_Device_Init service is complete. The service is in the
ICODE segment so it becomes invalid after the Init_Complete message. Calls
to the _AddInstanceItem service are also invalid after Init_Complete.
 
Do not use this service to instance devices added with the
DOSMGR_Add_Device service. To instance an added device, a virtual device
must call the _AddInstanceItem service or use the GVDAInstance flag in the
_Allocate_Global_V86_Data_Area service.
 
Uses
 
Flags
 
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