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include vmm.inc
 
mov     edx, OFFSET32 Filename  ; points to name of file to open
mov     edi, OFFSET32 Buffer    ; points to buffer to receive full path
VMMcall OpenFile
 
jc      not_found               ; carry flag is set if file not found
mov     [Handle], eax           ; MS-DOS file handle
 
The OpenFile service opens the file having the specified name. If the
Filename parameter specifies only a filename (no drive letter or path
separators included), this service searches for the file in the directories
specified by the following:
 
♦  WINDIR environment variable
 
♦  First command-line argument (argv[0]) of Windows
 
♦  Current working directory
 
♦  PATH environment variable
 
Otherwise, the service does not search for the file. In either case, the
service attempts to opens the file for reading (in compatibility mode), and
returns the MS-DOS file handle if it is successful.
 
This service is only available during initialization.
 
Parameter  Description
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Filename   Points to a null-terminated string specifying the name of the
           file to open.
 
Buffer     Points to a buffer that receives the full path of the file (if
           found). The buffer must be at least 128 bytes.
 
Return Value
 
If the carry flag is clear, the EAX register contains a valid MS-DOS file
handle (in the low word). The handle can be used in subsequent MS-DOS
functions to read from or close the file. If the carry flag is set, the file
cannot be found.
 
Comments
 
If WINDIR and PATH environment variables are not well formed, this service
cannot guarantee that the full path copied to the Buffer parameter will be
well formed.
 
This service fails if the current virtual machine cannot support a call to
the Exec_Int service, or if the virtual machine has already used the
_Allocate_Temp_V86_Data_Area service to allocate the temporary buffer.
 
Uses
 
EAX, Flags
 
See Also
 
_Allocate_Temp_V86_Data_Area, Exec_Int
 
 
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