gistfile1.m

#import "AppDelegate.h"

@implementation AppDelegate

- (void)applicationDidFinishLaunching:(NSNotification *)aNotification
{
    // Insert code here to initialize your application
    dispatch_queue_t the_queue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0);
    
    NSArray *array = [NSArray arrayWithObjects:@"a", @"b", @"c", @"d", @"e", @"f", nil];
    dispatch_apply(array.count, the_queue, ^(size_t i) {
        NSLog(@"%@", [array objectAtIndex:i]);
    });
    
    NSLog(@"done");
    
}

@end

/*
2012-11-21 13:57:17.077 test[46156:303] d
2012-11-21 13:57:17.077 test[46156:2707] a
2012-11-21 13:57:17.077 test[46156:1203] b
2012-11-21 13:57:17.077 test[46156:1803] c
2012-11-21 13:57:17.077 test[46156:6603] f
2012-11-21 13:57:17.077 test[46156:6403] e
2012-11-21 13:57:17.080 test[46156:303] done
*/