Save UIImage to Desktop on iOS Simulator

UIImage+RSSaveToDesktop.h

#if TARGET_IPHONE_SIMULATOR

@interface UIImage (RSSaveToDesktop)

/// Creates a RSUIImage directory on desktop and saves image to it.
-(void)rs_saveToDesktop;

/// Creates a RSUIImage directory on desktop and saves image to it with specified name.
-(void)rs_saveToDesktopWithName:(NSString *)customName;

@end

#endif

UIImage+RSSaveToDesktop.m

#if TARGET_IPHONE_SIMULATOR

#import <pwd.h>

static NSString *homeDirectory(){
    NSString *logname = [NSString stringWithCString:getenv("LOGNAME")
                                           encoding:NSUTF8StringEncoding];
    struct passwd *pw = getpwnam([logname UTF8String]);
	return pw
               ? [NSString stringWithCString:pw->pw_dir encoding:NSUTF8StringEncoding]
               : [@"/Users" stringByAppendingPathComponent:logname];
}

static NSString *createDesktopDirectory(){
    NSFileManager *fileManager = [NSFileManager defaultManager];
    NSString *basePath = [NSString
                          stringWithFormat:@"%@/Desktop/RSUIImage",homeDirectory()];
    NSUInteger n = 0;
    while (1) {
        ++n;
        NSString *path = n <=1
                         ? basePath
                         : [NSString stringWithFormat:@"%@ %u",basePath,n];
        BOOL isDirectory;
        BOOL exists = [fileManager fileExistsAtPath:path
                                        isDirectory:&isDirectory];
        if (exists && isDirectory) return path;
        if (!exists) {
            NSError *error;
            [fileManager createDirectoryAtPath:path
                   withIntermediateDirectories:NO
                                    attributes:nil
                                         error:&error];
            NSCAssert(NULL == error, nil);
            return path;
        }
    }
}

static NSString *snapshotPath(NSString *customName){
    if (!customName) customName = @"image";
    NSFileManager *fileManager = [NSFileManager defaultManager];
    NSString *directory = createDesktopDirectory();
    NSString *basePath = [directory stringByAppendingFormat:@"/%@.png",customName];
    NSUInteger n = 0;
    while (1) {
        ++n;
        NSString *path = n <=1
                         ? basePath
                         : [directory stringByAppendingFormat:@"/%@ %u.png",customName,n];
        BOOL exists = [fileManager fileExistsAtPath:path isDirectory:NULL];
        if (!exists) return path;
    }
}

@implementation UIImage (RSSaveToDesktop)

-(void)rs_saveToDesktop{
    return [self rs_saveToDesktopWithName:nil];
}

-(void)rs_saveToDesktopWithName:(NSString *)customName{
    NSFileManager *fileManager = [NSFileManager defaultManager];
    NSData *myImageData = UIImagePNGRepresentation(self);
    [fileManager createFileAtPath:snapshotPath(customName)
                         contents:myImageData
                       attributes:nil];
}

@end

#endif