Patent ID: 6269408
Filing Date: 2001-07-31
Classification: G06F

Abstract:
A method for creating a virtual device driver that is compatible with both first and second operating systems, said first and second operating systems respectively recognizing first and second sets of calls, only a portion of the calls of said second set being fully compatible with said first operating system, comprising the steps of:providing a primary virtual device driver having primary routines that make operating system calls that are fully compatible with said second operating system;appending supplementary logic and emulation routines to said primary virtual device driver, said supplementary logic being operable following execution of said primary virtual device driver under either said first or second operating systems, and said supplementary logic providing for determining under which of said two operating systems said primary virtual device driver is being executed;providing for said primary routines to function whenever said primary virtual device driver is executed under said second operating system and whenever said primary virtual device driver is executing under said first operating system and an operating system call corresponding to said portion of said second set of calls; andproviding for said emulation routines to function whenever said primary virtual device driver is executed under said first operating system and under an operating system call not corresponding to said portion of said second set of calls.