No pain,No gain

// Get Documents Directory

NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);

NSString *documentsDirectory = [paths objectAtIndex:0];

// Create Directory

NSString *tmpDir = [documentsDirectory stringByAppendingPathComponent:@"test_dir"];

mkdir([tmpDir cStringUsingEncoding:NSASCIIStringEncoding], 0777);

// Open File

NSString *tmpFile = [documentsDirectory stringByAppendingPathComponent:@"test_file.txt"];

FILE *file = fopen([tempFile cStringUsingEncoding:NSASCIIStringEncoding], "w");;