rws@EXPO.LCS.MIT.EDU (Bob Scheifler) (12/09/88)
1. Is there any way an application can make sure that only one copy of it is running on a host; For "host" do you mean client or display? If display, an application could, I suppose, store some identification of itself on a private property on a root window, for later instances to look at. Of course, you have to worry about having that property go away when the client terminals abnormally. I suppose another approach would be for the client to assert ownership of a private selection, which then would go away automatically when the client died. 2. Is there a way to prevent others users (on other hosts as well as the host on which the server's running) from opening up a window on the server while I am on? Nothing in R3, if I understand you correctly (viz. that you want user-based rather than host-based access control). On the Consortium staff machines here at MIT we have a simple connection-level authorization mechanism designed and implemented, which allows us to control connections to a finer grain than xhost. The code has (just) been distributed within the X Consortium for feedback. How much it will change, and whether the public will see something before R4, I can't commit to right now. (Nor can I commit to when R4 will be.)