This is a cocoa method for restarting a mac app

restartMacApp

+(void)restart:(id)sender
{
    NSString *restartScript = @"while ps -p $1 > /dev/null; do sleep 0.1; done; open \"$2\"";
    NSArray *arguments = [NSArray arrayWithObjects:
                          @"-c", restartScript,
                          @"",
                          [NSString stringWithFormat:@"%d",[[NSProcessInfo processInfo] processIdentifier]],
                          [[NSBundle mainBundle] bundlePath],
                          nil];
    [NSTask launchedTaskWithLaunchPath:@"/bin/sh" arguments:arguments];
    [NSApp terminate:self];
}