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include dosnet.inc
 
VxDcall DOSNET_Do_PSP_Adjust
 
The DOSNET_Do_PSP_Adjust service specifies whether the virtual device
requires unique PSP addresses for each virtual machine. The virtual MS-DOS
manager calls this service to determine whether it should adjust PSP
addresses for the virtual machines.
 
This service has no parameters.
 
Return Value
 
The carry flag is clear if the virtual MS-DOS manager should adjust the PSP.
Otherwise, the carry flag is set to prevent the virtual MS-DOS manager from
adjusting the PSP.
 
The EAX register contains zero if the virtual MS-DOS manager should check
the SYSTEM.INI file to determine whether to override the action specified by
the carry flag. Otherwise, the EAX register contains nonzero to prevent the
virtual device from checking the file.
 
Comments
 
A network that uses the MS-DOS PSP addresses as part of an ID should clear
the carry flag and return to direct the virtual MS-DOS manager to adjust PSP
addresses. The manager adjusts PSP addresses by starting each virtual
machine at a different paragraph address (using the virtual machine
identifier as the basis of the adjustment). Even so this technique does not
guaranteed unique PSP addresses. To ensure uniqueness, network software
should always use Get Current Virtual Machine ID (Interrupt 2Fh, Function
1683h) to retrieve the virtual machine identifier and use this identifier to
create an unique network ID.
 
Uses
 
EAX, Flags
 
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