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include vmm.inc
 
VMMcall _Allocate_Temp_V86_Data_Area, <nBytes, flags>
 
or      eax, eax        ; zero if error
jz      error
mov     [Address], eax  ; address of temporary block
 
The _Allocate_Temp_V86_Data_Area service allocates a block of memory from
the global V86 data area. The block is for exclusive use by the virtual
device during system initialization only. A virtual device typically
allocates a temporary block to serve as a buffer for calls to MS-DOS or BIOS
functions. A virtual device makes such calls using the Simulate_Int
service.
 
This service is only available during initialization.
 
Parameter  Description
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nBytes     Specifies the number of bytes to allocate.
 
flags      Specifies the operation flags. This parameter must be set to 0.
 
Return Value
 
The EAX register contains the ring-0 linear address of the block if the
service is successful. Otherwise, EAX contains zero to indicate an error
such as insufficient memory to satisfy the request or temporary area already
allocated.
 
Comments
 
This service always aligns the temporary block on a paragraph boundary and
fills the block with zeros.
 
Virtual devices must free the temporary block as soon as possible. The
system provides only one temporary data area, therefore only one temporary
block can be allocated at a time. Attempts to allocate a temporary block
when it is already allocated will result in an error.
 
Uses
 
EAX
 
See Also
 
_Free_Temp_V86_Data_Area
 
 
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