Patent ID: 7925751

Claim:
A method for operating a plurality of computers, comprising: maintaining a file on a selected computer of the plurality of computers; sending an open request for the file by a first computer of the plurality of computers to the selected computer, the open request including a first token generated by a client application instance on the first computer; opening the file for the first computer in response to the open request; distributing, by the client application instance, the first token to other client application instances within the plurality of computers, wherein each client application instance is an instance of a database management system; sending an open request for the file by a second computer of the plurality of computers to the selected computer, the open request including a second token; comparing the first token with the second token; if the first token and the second token match, granting the open request, wherein the first token allows access by each client application instance within the plurality of computers that possesses the same first token; and if the first token and the second token do not match, not opening the file for the second computer.