NSDictionary

	arrayKey
	
		string1
		string2
		string3
		string4
	
	dicKey
	
		key1
		object1
		key2
		object2
		key3
		object3
	
	key2
	object2
	key3
	object3

NSArray

	string1
	string2
	string3
	
		key1
		object1
		key2
		object2
		key3
		object3
	
	string5

At the end, after </plist>, there’s another CR.

writetofile API Reference

- (BOOL)writeToFile:(NSString *)path 
         atomically:(BOOL)useAuxiliaryFile;

Works with:

NSDictionary
NSArray
NSData
NSString

For more complicated purposes, NSOutputStream might be the best option, but for simply writing a date or even XML this might be the simplest and fasted way.

NSArray *paths = [[NSFileManager defaultManager] 
	directoryContentsAtPath: NSHomeDirectory()];

// either like that...
NSEnumerator *e = [paths objectEnumerator];
for (NSString *p in e) {
	NSLog(@"path: %@", p);
}

// or like that.
for (NSString *p in [paths objectEnumerator]) {
	NSLog(@"path: %@", p);
}

NSDictionary has both [myDict objectEnumerator] and [myDict keyEnumerator]. Fast Enumberation is a feature in Objective-C 2.0, it allows you to step over arrays and dictionaries in a fast, consice, and secure (guarded against mutations) manner.

for (NSString *p in paths) {
	NSLog(@"path: %@", p);
}

// or

NSString *p;
for (p in paths) {
	NSLog(@"path: %@", p);
}

Sometimes things are really as simple as they should be.