anti-deadlock system


application

	file transaction

	
		read
		write
		renew lock



operating system


	cancel a lock if

	
		there has been no 'renew-lock' event in the last 30 minutes, and

		there has been no file activity (read, write etc.) in the last 2 minutes


	consider a file-open to include a renew-lock event



read/writes

	if a lock has been cancelled, continue with the operation normally, however

	other applications could open the file and read/write to it.


		

	
		