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include vmm.inc
 
Begin_Service_Table DeviceName, DefSegment
 
The Begin_Service_Table macro marks the start of the service table for a
virtual device. A virtual device uses the service table to export the names
and addresses of its services. Other virtual devices can use the VxDcall
macro to call these services.
 
Parameter   Description
────────────────────────────────────────────────────────────────────────────
 
DeviceName  Specifies the name of the virtual device. This name is used to
            create a macro, named DeviceName_Service, that is used in the
            table to define each exported service. See the Comments section
            for a description of the macro.
 
DefSegment  Specifies the name of the data segment to place the table. This
            parameter is optional. If given, the macro uses the
            DefSegment_LOCKED_DATA_SEG macro to define the segment.
            Otherwise, it uses the VxD_LOCKED_DATA_SEG macro.
 
Return Value
 
This macro has no return value.
 
Comments
 
A virtual device exports its services by defining the symbol
Create_DeviceName_Service_Table before using the Begin_Service_Table macro.
Virtual devices that call these service also use the Begin_Service_Table
macro but must not define the Create_DeviceName_Service_Table symbol.
 
The complete service table has the following form:
 
Begin_Service_Table DeviceName, DefSegment
DeviceName_Service Procedure, LocalSeg
    .
    .
    .
End_Service_Table DeviceName, DefSegment
 
The DeviceName_Service macro, created by Begin_Service_Table, adds the
specified service to the table. A table may have any number of these
macros.
 
The Procedure parameter specifies the name of the service to add to the
table. If RESERVED is given, the macro reserves an entry in the table
instead adding a procedure.
 
The LocalSeg parameter specifies which segment contains the procedure. This
parameter is optional.
 
See Also
 
End_Service_Table, VxD_LOCKED_DATA_SEG
 
 
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