在clicocoa应用程序中,如何实现事件循环?

#import <Foundation/Foundation.h>
#import "Delegate.h"
#import <CoreLocation/CoreLocation.h>

int main (int argc, const char * argv[]) {
    NSAutoreleasePool * pool = [[NSAutoreleasePool alloc] init];

    Delegate *del = [Delegate alloc];

    CLLocationManager *locationManager;
    locationManager = [[CLLocationManager alloc] init];
    locationManager.delegate = del;
    [locationManager startUpdatingLocation];

    // Something goes here

    [pool drain];
    return 0;
}