Relaunching a cocoa app

Question

I have an application that checks its command line parameters and stores values in persistent stores. One of those is a password that I don't want sticking around for people to see with 'ps' and friends. The approach I'm currently looking at is to, after I've stored the values I need, relaunch the process without the command line parameters. My naive approach is this, where args[0] is the path to the application:

        NSTask *task = [[NSTask alloc] init];
        [task setLaunchPath:[args objectAtIndex:0]];
        [task launch];
        [task release];
        [NSApp terminate:nil];

The child is run. However, when my app is terminated the child doesn't seem to orphan but gets stuck. Am I just way off on this one?

More info: So it seems that when I call [NSApp terminate:nil] the NSTask that was launched gets stuck, but if I just exit() then it works fine. However, I'm concerned that things that are open (keychain, plist, etc.) will be in a bad state if I do that.

And note that lots of example code out there is about some watchdog-like process that restarts a separate process when needed. I'm trying to restart the current process that's already running from within that same process.

Answer 1

There are plenty of examples on the web, but this one looks like it has all the code you need. There are more detailed explanations out there, as well.

Answer 2

Use the keychain API for storing passwords. Don't re-invent the wheel.

Answer 3

Create an external process that launches yours when it terminates. Then terminate. Launching Cocoa programs with NSTask doesn't work quite right.

Answer 4

If you're using Sparkle in your project you can use their relaunch code rather than writing your own. I posted about it on my blog last month. http://blog.mbcharbonneau.com/2010/06/03/restart-your-cocoa-application-using-sparkle/