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include vmm.inc
 
mov     esi, OFFSET32 Variable  ; points to name of environment variable
VMMcall Get_Environment_String
 
jc      not_found               ; carry set if variable not found
mov     [Value], edx            ; points to value of environment variable
 
The Get_Environment_String service returns the value of the specified
environment variable.
 
This service is only available during initialization.
 
Parameter  Description
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Variable   Points to a null-terminated string specifying the name of an
           MS-DOS environment variable. This service is not sensitive to
           case, so the name may be given in any combination of uppercase
           and lowercase letters.
 
Return Value
 
The carry flag is clear and the EDX register points to a null-terminated
string specifying the value of the environment variable if the service is
successful. Otherwise, the carry flag is set to indicate that the
environment variable could not be found.
 
Comments
 
Environment variables, set using the MS-DOS set command, are a limited
resource. Although some virtual devices use environment variables as a way
to set operating parameters, this is not recommended unless the variable is
used by a set of programs, MS-DOS device drivers, and virtual devices.
 
Uses
 
EDX, Flags
 
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