There are a bunch of ways to do this, but the general principle is that when an instance of the app starts, it makes its presence known somehow (touching a file, broadcasting a distributed notification, vending a distributed object, etc). Then when a second instance starts, it tries to find a previous instance (looking for the file, broadcasting a distributed notification and waiting for a response, connecting to a distributed object, etc). If it finds one, it kills itself.
Dave On May 11, 2011, at 2:02 PM, Martin Batholdy wrote: > Hi, > > My program consists of a menu item and is NSUIagent - so it is hidden in the > Mac OS app-bar. > > Now what surprises me is that I am able to open several instances of this > program. > Every time I click on the app-file a new symbol appears and I have a new > instance of my program running. > > How can I prevent this? > (so that system-wide you can only have one instance of the program running) > > Is there a build-option in xCode for this? > > > thanks!_______________________________________________ > > Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) > > Please do not post admin requests or moderator comments to the list. > Contact the moderators at cocoa-dev-admins(at)lists.apple.com > > Help/Unsubscribe/Update your Subscription: > http://lists.apple.com/mailman/options/cocoa-dev/davedelong%40me.com > > This email sent to davedel...@me.com _______________________________________________ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
