如何确定Cocoa (OS X)应用程序启动时间

I'm writing an app for OS X, and I need to grab messages from the log to send back to our server for analysis/troubleshooting. I know I can use the Apple System Log (ASL) functions to get what I want, but would like to only get log messages for the current session. I could grab the time in my AppDelegate init method:I'm writing an app for OS X, and I need to grab