基于OSX系统中的文件编程

　　OSX提供的API都是面向对象的，是基于ObjectC语言的，在OSX中文件的操作可以通过标准C语言提供的接口，fread,fwrite,fseek，通过这几个接口基本上可以完成文件的读写功能。

　　还有一些delete文件的接口是由UNIX提供的，因为OSX是基于UNIX的，UNIX中的接口在OSX中也是可以使用的，我们使用的一些系统级别的API也只是OSX对UNIX的API封装而已，因为封装的不错，所以，我们最好还是使用OSX提供的API才操作文件。

　　在OSX中，对文件的操作都是由NSFileManager来完成的。下面我贴出来NSFileManager.h头文件。

　　

/*    NSFileManager.h
    Copyright (c) 1994-2013, Apple Inc. All rights reserved.
*/

#import <Foundation/NSObject.h>
#import <Foundation/NSEnumerator.h>
#import <Foundation/NSDictionary.h>
#import <Foundation/NSPathUtilities.h>
#import <CoreFoundation/CFBase.h>

@class NSArray, NSData, NSDate, NSDirectoryEnumerator, NSError, NSNumber;
@protocol NSFileManagerDelegate;

/* Version number where NSFileManager can copy/move/enumerate resources forks correctly. 
*/
#define NSFoundationVersionWithFileManagerResourceForkSupport 412

typedef NS_OPTIONS(NSUInteger, NSVolumeEnumerationOptions) {
    /* The mounted volume enumeration will skip hidden volumes.
     */
    NSVolumeEnumerationSkipHiddenVolumes = 1UL << 1,
    
    /* The mounted volume enumeration will produce file reference URLs rather than path-based URLs.
     */
    NSVolumeEnumerationProduceFileReferenceURLs = 1UL << 2
} NS_ENUM_AVAILABLE(10_6, 4_0);

typedef NS_OPTIONS(NSUInteger, NSDirectoryEnumerationOptions) {
    /* NSDirectoryEnumerationSkipsSubdirectoryDescendants causes the NSDirectoryEnumerator to perform a shallow enumeration and not descend into directories it encounters.
     */
    NSDirectoryEnumerationSkipsSubdirectoryDescendants = 1UL << 0,
    
    /* NSDirectoryEnumerationSkipsPackageDescendants will cause the NSDirectoryEnumerator to not descend into packages.
     */
    NSDirectoryEnumerationSkipsPackageDescendants      = 1UL << 1,
    
    /* NSDirectoryEnumerationSkipsHiddenFiles causes the NSDirectoryEnumerator to not enumerate hidden files.
     */
    NSDirectoryEnumerationSkipsHiddenFiles             = 1UL << 2
} NS_ENUM_AVAILABLE(10_6, 4_0);

typedef NS_OPTIONS(NSUInteger, NSFileManagerItemReplacementOptions) {
    /* NSFileManagerItemReplacementUsingNewMetadataOnly causes -replaceItemAtURL:withItemAtURL:backupItemName:options:resultingItemURL:error: to use metadata from the new item only and not to attempt to preserve metadata from the original item.
     */
    NSFileManagerItemReplacementUsingNewMetadataOnly = 1UL << 0,
    
    /* NSFileManagerItemReplacementWithoutDeletingBackupItem causes -replaceItemAtURL:withItemAtURL:backupItemName:options:resultingItemURL:error: to leave the backup item in place after a successful replacement. The default behavior is to remove the item.
     */
     NSFileManagerItemReplacementWithoutDeletingBackupItem = 1UL << 1
} NS_ENUM_AVAILABLE(10_6, 4_0);

/* Notification sent after the current ubiquity identity has changed.
*/
extern NSString * const NSUbiquityIdentityDidChangeNotification NS_AVAILABLE(10_8, 6_0);
/*
　　
这里就是NSFileManager

*/

@interface NSFileManager : NSObject

/*
 　　这里可以看出来NSFileManager是单例
　　Returns the default singleton instance.
*/
+ (NSFileManager *)defaultManager;

/* -mountedVolumeURLsIncludingResourceValuesForKeys:options: returns an NSArray of NSURLs locating the mounted volumes available on the computer. The property keys that can be requested are available in <Foundation/NSURL.h>.
 */
- (NSArray *)mountedVolumeURLsIncludingResourceValuesForKeys:(NSArray *)propertyKeys options:(NSVolumeEnumerationOptions)options NS_AVAILABLE(10_6, 4_0);

/* -contentsOfDirectoryAtURL:includingPropertiesForKeys:options:error: returns an NSArray of NSURLs identifying the the directory entries. If this method returns nil, an NSError will be returned by reference in the 'error' parameter. If the directory contains no entries, this method will return the empty array. When an array is specified for the 'keys' parameter, the specified property values will be pre-fetched and cached with each enumerated URL.
 
    This method always does a shallow enumeration of the specified directory (i.e. it always acts as if NSDirectoryEnumerationSkipsSubdirectoryDescendants has been specified). If you need to perform a deep enumeration, use -[NSFileManager enumeratorAtURL:includingPropertiesForKeys:options:errorHandler:].
 
    If you wish to only receive the URLs and no other attributes, then pass '0' for 'options' and an empty NSArray ('[NSArray array]') for 'keys'. If you wish to have the property caches of the vended URLs pre-populated with a default set of attributes, then pass '0' for 'options' and 'nil' for 'keys'.
 */
- (NSArray *)contentsOfDirectoryAtURL:(NSURL *)url includingPropertiesForKeys:(NSArray *)keys options:(NSDirectoryEnumerationOptions)mask error:(NSError **)error NS_AVAILABLE(10_6, 4_0);


/* -URLsForDirectory:inDomains: is analogous to NSSearchPathForDirectoriesInDomains(), but returns an array of NSURL instances for use with URL-taking APIs. This API is suitable when you need to search for a file or files which may live in one of a variety of locations in the domains specified.
 */
- (NSArray *)URLsForDirectory:(NSSearchPathDirectory)directory inDomains:(NSSearchPathDomainMask)domainMask NS_AVAILABLE(10_6, 4_0);

/* -URLForDirectory:inDomain:appropriateForURL:create:error: is a URL-based replacement for FSFindFolder(). It allows for the specification and (optional) creation of a specific directory for a particular purpose (e.g. the replacement of a particular item on disk, or a particular Library directory.
 
    You may pass only one of the values from the NSSearchPathDomainMask enumeration, and you may not pass NSAllDomainsMask.
 */
- (NSURL *)URLForDirectory:(NSSearchPathDirectory)directory inDomain:(NSSearchPathDomainMask)domain appropriateForURL:(NSURL *)url create:(BOOL)shouldCreate error:(NSError **)error NS_AVAILABLE(10_6, 4_0);

/* createDirectoryAtURL:withIntermediateDirectories:attributes:error: creates a directory at the specified URL. If you pass 'NO' for withIntermediateDirectories, the directory must not exist at the time this call is made. Passing 'YES' for withIntermediateDirectories will create any necessary intermediate directories. This method returns YES if all directories specified in 'url' were created and attributes were set. Directories are created with attributes specified by the dictionary passed to 'attributes'. If no dictionary is supplied, directories are created according to the umask of the process. This method returns NO if a failure occurs at any stage of the operation. If an error parameter was provided, a presentable NSError will be returned by reference.
 */
- (BOOL)createDirectoryAtURL:(NSURL *)url withIntermediateDirectories:(BOOL)createIntermediates attributes:(NSDictionary *)attributes error:(NSError **)error NS_AVAILABLE(10_7, 5_0);

/* createSymbolicLinkAtURL:withDestinationURL:error: returns YES if the symbolic link that point at 'destURL' was able to be created at the location specified by 'url'. 'destURL' is always resolved against its base URL, if it has one. If 'destURL' has no base URL and it's 'relativePath' is indeed a relative path, then a relative symlink will be created. If this method returns NO, the link was unable to be created and an NSError will be returned by reference in the 'error' parameter. This method does not traverse a terminal symlink.
 */
- (BOOL)createSymbolicLinkAtURL:(NSURL *)url withDestinationURL:(NSURL *)destURL error:(NSError **)error NS_AVAILABLE(10_7, 5_0);

/* Instances of NSFileManager may now have delegates. Each instance has one delegate, and the delegate is not retained. In versions of Mac OS X prior to 10.5, the behavior of calling [[NSFileManager alloc] init] was undefined. In Mac OS X 10.5 "Leopard" and later, calling [[NSFileManager alloc] init] returns a new instance of an NSFileManager.
 */
- (void)setDelegate:(id)delegate NS_AVAILABLE(10_5, 2_0);
- (id)delegate NS_AVAILABLE(10_5, 2_0);

/* setAttributes:ofItemAtPath:error: returns YES when the attributes specified in the 'attributes' dictionary are set successfully on the item specified by 'path'. If this method returns NO, a presentable NSError will be provided by-reference in the 'error' parameter. If no error is required, you may pass 'nil' for the error.
 
    This method replaces changeFileAttributes:atPath:.
 */
- (BOOL)setAttributes:(NSDictionary *)attributes ofItemAtPath:(NSString *)path error:(NSError **)error NS_AVAILABLE(10_5, 2_0);

/* createDirectoryAtPath:withIntermediateDirectories:attributes:error: creates a directory at the specified path. If you pass 'NO' for createIntermediates, the directory must not exist at the time this call is made. Passing 'YES' for 'createIntermediates' will create any necessary intermediate directories. This method returns YES if all directories specified in 'path' were created and attributes were set. Directories are created with attributes specified by the dictionary passed to 'attributes'. If no dictionary is supplied, directories are created according to the umask of the process. This method returns NO if a failure occurs at any stage of the operation. If an error parameter was provided, a presentable NSError will be returned by reference.
 
    This method replaces createDirectoryAtPath:attributes:
 */
- (BOOL)createDirectoryAtPath:(NSString *)path withIntermediateDirectories:(BOOL)createIntermediates attributes:(NSDictionary *)attributes error:(NSError **)error NS_AVAILABLE(10_5, 2_0);

/* contentsOfDirectoryAtPath:error: returns an NSArray of NSStrings representing the filenames of the items in the directory. If this method returns 'nil', an NSError will be returned by reference in the 'error' parameter. If the directory contains no items, this method will return the empty array.
 
    This method replaces directoryContentsAtPath:
 */
- (NSArray *)contentsOfDirectoryAtPath:(NSString *)path error:(NSError **)error NS_AVAILABLE(10_5, 2_0);

/* subpathsOfDirectoryAtPath:error: returns an NSArray of NSStrings representing the filenames of the items in the specified directory and all its subdirectories recursively. If this method returns 'nil', an NSError will be returned by reference in the 'error' parameter. If the directory contains no items, this method will return the empty array.
 
    This method replaces subpathsAtPath:
 */
- (NSArray *)subpathsOfDirectoryAtPath:(NSString *)path error:(NSError **)error NS_AVAILABLE(10_5, 2_0);

/* attributesOfItemAtPath:error: returns an NSDictionary of key/value pairs containing the attributes of the item (file, directory, symlink, etc.) at the path in question. If this method returns 'nil', an NSError will be returned by reference in the 'error' parameter. This method does not traverse a terminal symlink.
 
    This method replaces fileAttributesAtPath:traverseLink:.
 */
- (NSDictionary *)attributesOfItemAtPath:(NSString *)path error:(NSError **)error NS_AVAILABLE(10_5, 2_0);

/* attributesOfFileSystemForPath:error: returns an NSDictionary of key/value pairs containing the attributes of the filesystem containing the provided path. If this method returns 'nil', an NSError will be returned by reference in the 'error' parameter. This method does not traverse a terminal symlink.
 
    This method replaces fileSystemAttributesAtPath:.
 */
- (NSDictionary *)attributesOfFileSystemForPath:(NSString *)path error:(NSError **)error NS_AVAILABLE(10_5, 2_0);

/* createSymbolicLinkAtPath:withDestination:error: returns YES if the symbolic link that point at 'destPath' was able to be created at the location specified by 'path'. If this method returns NO, the link was unable to be created and an NSError will be returned by reference in the 'error' parameter. This method does not traverse a terminal symlink.
 
    This method replaces createSymbolicLinkAtPath:pathContent:
 */
- (BOOL)createSymbolicLinkAtPath:(NSString *)path withDestinationPath:(NSString *)destPath error:(NSError **)error NS_AVAILABLE(10_5, 2_0);

/* destinationOfSymbolicLinkAtPath:error: returns an NSString containing the path of the item pointed at by the symlink specified by 'path'. If this method returns 'nil', an NSError will be returned by reference in the 'error' parameter.
 
    This method replaces pathContentOfSymbolicLinkAtPath:
 */
- (NSString *)destinationOfSymbolicLinkAtPath:(NSString *)path error:(NSError **)error NS_AVAILABLE(10_5, 2_0);

/* These methods replace their non-error returning counterparts below. See the NSFileManagerFileOperationAdditions category below for methods that are dispatched to the NSFileManager instance's delegate.
 */
- (BOOL)copyItemAtPath:(NSString *)srcPath toPath:(NSString *)dstPath error:(NSError **)error NS_AVAILABLE(10_5, 2_0);
- (BOOL)moveItemAtPath:(NSString *)srcPath toPath:(NSString *)dstPath error:(NSError **)error NS_AVAILABLE(10_5, 2_0);
- (BOOL)linkItemAtPath:(NSString *)srcPath toPath:(NSString *)dstPath error:(NSError **)error NS_AVAILABLE(10_5, 2_0);
- (BOOL)removeItemAtPath:(NSString *)path error:(NSError **)error NS_AVAILABLE(10_5, 2_0);

/* These methods are URL-taking equivalents of the four methods above. Their delegate methods are defined in the NSFileManagerFileOperationAdditions category below.
 */
- (BOOL)copyItemAtURL:(NSURL *)srcURL toURL:(NSURL *)dstURL error:(NSError **)error NS_AVAILABLE(10_6, 4_0);
- (BOOL)moveItemAtURL:(NSURL *)srcURL toURL:(NSURL *)dstURL error:(NSError **)error NS_AVAILABLE(10_6, 4_0);
- (BOOL)linkItemAtURL:(NSURL *)srcURL toURL:(NSURL *)dstURL error:(NSError **)error NS_AVAILABLE(10_6, 4_0);
- (BOOL)removeItemAtURL:(NSURL *)URL error:(NSError **)error NS_AVAILABLE(10_6, 4_0);

/* trashItemAtURL:resultingItemURL:error: returns YES if the item at 'url' was successfully moved to a Trash. Since the operation may require renaming the file to avoid collisions, it also returns by reference the resulting URL that the item was moved to. If this method returns NO, the item was not moved and an NSError will be returned by reference in the 'error' parameter.
 */
- (BOOL)trashItemAtURL:(NSURL *)url resultingItemURL:(NSURL **)outResultingURL error:(NSError **)error NS_AVAILABLE_MAC(10_8);

/* The following methods are deprecated on Mac OS X 10.5. Their URL-based and/or error-returning replacements are listed above.
 */
- (NSDictionary *)fileAttributesAtPath:(NSString *)path traverseLink:(BOOL)yorn NS_DEPRECATED(10_0, 10_5, 2_0, 2_0);
- (BOOL)changeFileAttributes:(NSDictionary *)attributes atPath:(NSString *)path NS_DEPRECATED(10_0, 10_5, 2_0, 2_0);
- (NSArray *)directoryContentsAtPath:(NSString *)path NS_DEPRECATED(10_0, 10_5, 2_0, 2_0);
- (NSDictionary *)fileSystemAttributesAtPath:(NSString *)path NS_DEPRECATED(10_0, 10_5, 2_0, 2_0);
- (NSString *)pathContentOfSymbolicLinkAtPath:(NSString *)path NS_DEPRECATED(10_0, 10_5, 2_0, 2_0);
- (BOOL)createSymbolicLinkAtPath:(NSString *)path pathContent:(NSString *)otherpath NS_DEPRECATED(10_0, 10_5, 2_0, 2_0);
- (BOOL)createDirectoryAtPath:(NSString *)path attributes:(NSDictionary *)attributes NS_DEPRECATED(10_0, 10_5, 2_0, 2_0);

#if (TARGET_OS_MAC && !(TARGET_OS_EMBEDDED || TARGET_OS_IPHONE)) || TARGET_OS_WIN32
- (BOOL)linkPath:(NSString *)src toPath:(NSString *)dest handler:(id)handler NS_DEPRECATED(10_0, 10_5, 2_0, 2_0);
- (BOOL)copyPath:(NSString *)src toPath:(NSString *)dest handler:(id)handler NS_DEPRECATED(10_0, 10_5, 2_0, 2_0);
- (BOOL)movePath:(NSString *)src toPath:(NSString *)dest handler:(id)handler NS_DEPRECATED(10_0, 10_5, 2_0, 2_0);
- (BOOL)removeFileAtPath:(NSString *)path handler:(id)handler NS_DEPRECATED(10_0, 10_5, 2_0, 2_0);
#endif

/* Process working directory management. Despite the fact that these are instance methods on NSFileManager, these methods report and change (respectively) the working directory for the entire process. Developers are cautioned that doing so is fraught with peril.
 */
- (NSString *)currentDirectoryPath;
- (BOOL)changeCurrentDirectoryPath:(NSString *)path;

/* The following methods are of limited utility. Attempting to predicate behavior based on the current state of the filesystem or a particular file on the filesystem is encouraging odd behavior in the face of filesystem race conditions. It's far better to attempt an operation (like loading a file or creating a directory) and handle the error gracefully than it is to try to figure out ahead of time whether the operation will succeed.
 */
- (BOOL)fileExistsAtPath:(NSString *)path;
- (BOOL)fileExistsAtPath:(NSString *)path isDirectory:(BOOL *)isDirectory;
- (BOOL)isReadableFileAtPath:(NSString *)path;
- (BOOL)isWritableFileAtPath:(NSString *)path;
- (BOOL)isExecutableFileAtPath:(NSString *)path;
- (BOOL)isDeletableFileAtPath:(NSString *)path;

/* -contentsEqualAtPath:andPath: does not take into account data stored in the resource fork or filesystem extended attributes.
 */
- (BOOL)contentsEqualAtPath:(NSString *)path1 andPath:(NSString *)path2;

/* displayNameAtPath: returns an NSString suitable for presentation to the user. For directories which have localization information, this will return the appropriate localized string. This string is not suitable for passing to anything that must interact with the filesystem.
 */
- (NSString *)displayNameAtPath:(NSString *)path;

/* componentsToDisplayForPath: returns an NSArray of display names for the path provided. Localization will occur as in displayNameAtPath: above. This array cannot and should not be reassembled into an usable filesystem path for any kind of access.
 */
- (NSArray *)componentsToDisplayForPath:(NSString *)path;

/* enumeratorAtPath: returns an NSDirectoryEnumerator rooted at the provided path. If the enumerator cannot be created, this returns NULL. Because NSDirectoryEnumerator is a subclass of NSEnumerator, the returned object can be used in the for...in construct.
 */
- (NSDirectoryEnumerator *)enumeratorAtPath:(NSString *)path;

#if NS_BLOCKS_AVAILABLE
/* enumeratorAtURL:includingPropertiesForKeys:options:errorHandler: returns an NSDirectoryEnumerator rooted at the provided directory URL. The NSDirectoryEnumerator returns NSURLs from the -nextObject method. The optional 'includingPropertiesForKeys' parameter indicates which resource properties should be pre-fetched and cached with each enumerated URL. The optional 'errorHandler' block argument is invoked when an error occurs. Parameters to the block are the URL on which an error occurred and the error. When the error handler returns YES, enumeration continues if possible. Enumeration stops immediately when the error handler returns NO.

    If you wish to only receive the URLs and no other attributes, then pass '0' for 'options' and an empty NSArray ('[NSArray array]') for 'keys'. If you wish to have the property caches of the vended URLs pre-populated with a default set of attributes, then pass '0' for 'options' and 'nil' for 'keys'.
 */
- (NSDirectoryEnumerator *)enumeratorAtURL:(NSURL *)url includingPropertiesForKeys:(NSArray *)keys options:(NSDirectoryEnumerationOptions)mask errorHandler:(BOOL (^)(NSURL *url, NSError *error))handler NS_AVAILABLE(10_6, 4_0);
#endif

/* subpathsAtPath: returns an NSArray of all contents and subpaths recursively from the provided path. This may be very expensive to compute for deep filesystem hierarchies, and should probably be avoided.
 */
- (NSArray *)subpathsAtPath:(NSString *)path;

/* These methods are provided here for compatibility. The corresponding methods on NSData which return NSErrors should be regarded as the primary method of creating a file from an NSData or retrieving the contents of a file as an NSData.
 */
- (NSData *)contentsAtPath:(NSString *)path;
- (BOOL)createFileAtPath:(NSString *)path contents:(NSData *)data attributes:(NSDictionary *)attr;

/* fileSystemRepresentationWithPath: returns an array of characters suitable for passing to lower-level POSIX style APIs. The string is provided in the representation most appropriate for the filesystem in question.
 */
- (__strong const char *)fileSystemRepresentationWithPath:(NSString *)path NS_RETURNS_INNER_POINTER;

/* stringWithFileSystemRepresentation:length: returns an NSString created from an array of bytes that are in the filesystem representation.
 */
- (NSString *)stringWithFileSystemRepresentation:(const char *)str length:(NSUInteger)len;

/* -replaceItemAtURL:withItemAtURL:backupItemName:options:resultingItemURL:error: is for developers who wish to perform a safe-save without using the full NSDocument machinery that is available in the AppKit.
 
    The `originalItemURL` is the item being replaced.
    `newItemURL` is the item which will replace the original item. This item should be placed in a temporary directory as provided by the OS, or in a uniquely named directory placed in the same directory as the original item if the temporary directory is not available.
    If `backupItemName` is provided, that name will be used to create a backup of the original item. The backup is placed in the same directory as the original item. If an error occurs during the creation of the backup item, the operation will fail. If there is already an item with the same name as the backup item, that item will be removed. The backup item will be removed in the event of success unless the `NSFileManagerItemReplacementWithoutDeletingBackupItem` option is provided in `options`.
    For `options`, pass `0` to get the default behavior, which uses only the metadata from the new item while adjusting some properties using values from the original item. Pass `NSFileManagerItemReplacementUsingNewMetadataOnly` in order to use all possible metadata from the new item.
 */
- (BOOL)replaceItemAtURL:(NSURL *)originalItemURL withItemAtURL:(NSURL *)newItemURL backupItemName:(NSString *)backupItemName options:(NSFileManagerItemReplacementOptions)options resultingItemURL:(NSURL **)resultingURL error:(NSError **)error NS_AVAILABLE(10_6, 4_0);


/* Changes whether the item for the specified URL is ubiquitous and moves the item to the destination URL. When making an item ubiquitous, the destination URL must be prefixed with a URL from -URLForUbiquityContainerIdentifier:. Returns YES if the change is successful, NO otherwise.
 */
- (BOOL)setUbiquitous:(BOOL)flag itemAtURL:(NSURL *)url destinationURL:(NSURL *)destinationURL error:(NSError **)error NS_AVAILABLE(10_7, 5_0);

/* Returns YES if the item for the specified URL is ubiquitous, NO otherwise.
 */
- (BOOL)isUbiquitousItemAtURL:(NSURL *)url NS_AVAILABLE(10_7, 5_0);

/* Start downloading a local instance of the specified ubiquitous item, if necessary. Returns YES if the download started successfully or wasn't necessary, NO otherwise.
 */
- (BOOL)startDownloadingUbiquitousItemAtURL:(NSURL *)url error:(NSError **)error NS_AVAILABLE(10_7, 5_0);

/* Removes the local instance of the ubiquitous item at the given URL. Returns YES if removal was successful, NO otherwise.
 */
- (BOOL)evictUbiquitousItemAtURL:(NSURL *)url error:(NSError **)error NS_AVAILABLE(10_7, 5_0);

/* Returns a file URL for the root of the ubiquity container directory corresponding to the supplied container ID. Returns nil if the mobile container does not exist or could not be determined.
 */
- (NSURL *)URLForUbiquityContainerIdentifier:(NSString *)containerIdentifier NS_AVAILABLE(10_7, 5_0);

/* Returns a URL that can be shared with other users to allow them download a copy of the specified ubiquitous item. Also returns the date after which the item will no longer be accessible at the returned URL. The URL must be prefixed with a URL from -URLForUbiquityContainerIdentifier:.
 */
- (NSURL *)URLForPublishingUbiquitousItemAtURL:(NSURL *)url expirationDate:(NSDate **)outDate error:(NSError **)error NS_AVAILABLE(10_7, 5_0);

/* Returns an opaque token that represents the current ubiquity identity. This object can be copied, encoded, or compared with isEqual:. When ubiquity containers are unavailable because the user has disabled them, or when the user is simply not logged in, this method will return nil. The NSUbiquityIdentityDidChangeNotification notification is posted after this value changes.

    If you don't need the container URL and just want to check if ubiquity containers are available you should use this method instead of checking -URLForUbiquityContainerIdentifier:.
*/
- (id <NSObject, NSCopying, NSCoding>)ubiquityIdentityToken NS_AVAILABLE(10_8, 6_0);

/* Returns the container directory associated with the specified security application group ID.
 */
- (NSURL *)containerURLForSecurityApplicationGroupIdentifier:(NSString *)groupIdentifier NS_AVAILABLE(10_8, 7_0); // Available for OS X in 10.8.3.


@end

/* These delegate methods are for the use of the deprecated handler-taking methods on NSFileManager for copying, moving, linking or deleting files.
 */
@interface NSObject (NSCopyLinkMoveHandler)
- (BOOL)fileManager:(NSFileManager *)fm shouldProceedAfterError:(NSDictionary *)errorInfo NS_DEPRECATED(10_0, 10_5, 2_0, 2_0);
- (void)fileManager:(NSFileManager *)fm willProcessPath:(NSString *)path NS_DEPRECATED(10_0, 10_5, 2_0, 2_0);
@end


@protocol NSFileManagerDelegate <NSObject>
@optional

/* fileManager:shouldCopyItemAtPath:toPath: gives the delegate an opportunity to filter the resulting copy. Returning YES from this method will allow the copy to happen. Returning NO from this method causes the item in question to be skipped. If the item skipped was a directory, no children of that directory will be copied, nor will the delegate be notified of those children.

    If the delegate does not implement this method, the NSFileManager instance acts as if this method returned YES.
 */
- (BOOL)fileManager:(NSFileManager *)fileManager shouldCopyItemAtPath:(NSString *)srcPath toPath:(NSString *)dstPath;
- (BOOL)fileManager:(NSFileManager *)fileManager shouldCopyItemAtURL:(NSURL *)srcURL toURL:(NSURL *)dstURL NS_AVAILABLE(10_6, 4_0);

/* fileManager:shouldProceedAfterError:copyingItemAtPath:toPath: gives the delegate an opportunity to recover from or continue copying after an error. If an error occurs, the error object will contain an NSError indicating the problem. The source path and destination paths are also provided. If this method returns YES, the NSFileManager instance will continue as if the error had not occurred. If this method returns NO, the NSFileManager instance will stop copying, return NO from copyItemAtPath:toPath:error: and the error will be provied there.

    If the delegate does not implement this method, the NSFileManager instance acts as if this method returned NO.
 */
- (BOOL)fileManager:(NSFileManager *)fileManager shouldProceedAfterError:(NSError *)error copyingItemAtPath:(NSString *)srcPath toPath:(NSString *)dstPath;
- (BOOL)fileManager:(NSFileManager *)fileManager shouldProceedAfterError:(NSError *)error copyingItemAtURL:(NSURL *)srcURL toURL:(NSURL *)dstURL NS_AVAILABLE(10_6, 4_0);

/* fileManager:shouldMoveItemAtPath:toPath: gives the delegate an opportunity to not move the item at the specified path. If the source path and the destination path are not on the same device, a copy is performed to the destination path and the original is removed. If the copy does not succeed, an error is returned and the incomplete copy is removed, leaving the original in place.

    If the delegate does not implement this method, the NSFileManager instance acts as if this method returned YES.
 */
- (BOOL)fileManager:(NSFileManager *)fileManager shouldMoveItemAtPath:(NSString *)srcPath toPath:(NSString *)dstPath;
- (BOOL)fileManager:(NSFileManager *)fileManager shouldMoveItemAtURL:(NSURL *)srcURL toURL:(NSURL *)dstURL NS_AVAILABLE(10_6, 4_0);

/* fileManager:shouldProceedAfterError:movingItemAtPath:toPath: functions much like fileManager:shouldProceedAfterError:copyingItemAtPath:toPath: above. The delegate has the opportunity to remedy the error condition and allow the move to continue.

    If the delegate does not implement this method, the NSFileManager instance acts as if this method returned NO.
 */
- (BOOL)fileManager:(NSFileManager *)fileManager shouldProceedAfterError:(NSError *)error movingItemAtPath:(NSString *)srcPath toPath:(NSString *)dstPath;
- (BOOL)fileManager:(NSFileManager *)fileManager shouldProceedAfterError:(NSError *)error movingItemAtURL:(NSURL *)srcURL toURL:(NSURL *)dstURL NS_AVAILABLE(10_6, 4_0);

/* fileManager:shouldLinkItemAtPath:toPath: acts as the other "should" methods, but this applies to the file manager creating hard links to the files in question.

    If the delegate does not implement this method, the NSFileManager instance acts as if this method returned YES.
 */
- (BOOL)fileManager:(NSFileManager *)fileManager shouldLinkItemAtPath:(NSString *)srcPath toPath:(NSString *)dstPath;
- (BOOL)fileManager:(NSFileManager *)fileManager shouldLinkItemAtURL:(NSURL *)srcURL toURL:(NSURL *)dstURL NS_AVAILABLE(10_6, 4_0);

/* fileManager:shouldProceedAfterError:linkingItemAtPath:toPath: allows the delegate an opportunity to remedy the error which occurred in linking srcPath to dstPath. If the delegate returns YES from this method, the linking will continue. If the delegate returns NO from this method, the linking operation will stop and the error will be returned via linkItemAtPath:toPath:error:.

    If the delegate does not implement this method, the NSFileManager instance acts as if this method returned NO.
 */
- (BOOL)fileManager:(NSFileManager *)fileManager shouldProceedAfterError:(NSError *)error linkingItemAtPath:(NSString *)srcPath toPath:(NSString *)dstPath;
- (BOOL)fileManager:(NSFileManager *)fileManager shouldProceedAfterError:(NSError *)error linkingItemAtURL:(NSURL *)srcURL toURL:(NSURL *)dstURL NS_AVAILABLE(10_6, 4_0);

/* fileManager:shouldRemoveItemAtPath: allows the delegate the opportunity to not remove the item at path. If the delegate returns YES from this method, the NSFileManager instance will attempt to remove the item. If the delegate returns NO from this method, the remove skips the item. If the item is a directory, no children of that item will be visited.

    If the delegate does not implement this method, the NSFileManager instance acts as if this method returned YES.
 */
- (BOOL)fileManager:(NSFileManager *)fileManager shouldRemoveItemAtPath:(NSString *)path;
- (BOOL)fileManager:(NSFileManager *)fileManager shouldRemoveItemAtURL:(NSURL *)URL NS_AVAILABLE(10_6, 4_0);

/* fileManager:shouldProceedAfterError:removingItemAtPath: allows the delegate an opportunity to remedy the error which occurred in removing the item at the path provided. If the delegate returns YES from this method, the removal operation will continue. If the delegate returns NO from this method, the removal operation will stop and the error will be returned via linkItemAtPath:toPath:error:.

    If the delegate does not implement this method, the NSFileManager instance acts as if this method returned NO.
 */
- (BOOL)fileManager:(NSFileManager *)fileManager shouldProceedAfterError:(NSError *)error removingItemAtPath:(NSString *)path;
- (BOOL)fileManager:(NSFileManager *)fileManager shouldProceedAfterError:(NSError *)error removingItemAtURL:(NSURL *)URL NS_AVAILABLE(10_6, 4_0);

@end


@interface NSDirectoryEnumerator : NSEnumerator

/* For NSDirectoryEnumerators created with -enumeratorAtPath:, the -fileAttributes and -directoryAttributes methods return an NSDictionary containing the keys listed below. For NSDirectoryEnumerators created with -enumeratorAtURL:includingPropertiesForKeys:options:errorHandler:, these two methods return nil.
 */
- (NSDictionary *)fileAttributes;
- (NSDictionary *)directoryAttributes;

- (void)skipDescendents;

/* This method returns the number of levels deep the current object is in the directory hierarchy being enumerated. The directory passed to -enumeratorAtURL:includingPropertiesForKeys:options:errorHandler: is considered to be level 0.
 */
- (NSUInteger)level NS_AVAILABLE(10_6, 4_0);

/* This method is spelled correctly.
 */
- (void)skipDescendants NS_AVAILABLE(10_6, 4_0);

@end

FOUNDATION_EXPORT NSString * const NSFileType;
FOUNDATION_EXPORT NSString * const NSFileTypeDirectory;
FOUNDATION_EXPORT NSString * const NSFileTypeRegular;
FOUNDATION_EXPORT NSString * const NSFileTypeSymbolicLink;
FOUNDATION_EXPORT NSString * const NSFileTypeSocket;
FOUNDATION_EXPORT NSString * const NSFileTypeCharacterSpecial;
FOUNDATION_EXPORT NSString * const NSFileTypeBlockSpecial;
FOUNDATION_EXPORT NSString * const NSFileTypeUnknown;
FOUNDATION_EXPORT NSString * const NSFileSize;
FOUNDATION_EXPORT NSString * const NSFileModificationDate;
FOUNDATION_EXPORT NSString * const NSFileReferenceCount;
FOUNDATION_EXPORT NSString * const NSFileDeviceIdentifier;
FOUNDATION_EXPORT NSString * const NSFileOwnerAccountName;
FOUNDATION_EXPORT NSString * const NSFileGroupOwnerAccountName;
FOUNDATION_EXPORT NSString * const NSFilePosixPermissions;
FOUNDATION_EXPORT NSString * const NSFileSystemNumber;
FOUNDATION_EXPORT NSString * const NSFileSystemFileNumber;
FOUNDATION_EXPORT NSString * const NSFileExtensionHidden;
FOUNDATION_EXPORT NSString * const NSFileHFSCreatorCode;
FOUNDATION_EXPORT NSString * const NSFileHFSTypeCode;
FOUNDATION_EXPORT NSString * const NSFileImmutable;
FOUNDATION_EXPORT NSString * const NSFileAppendOnly;
FOUNDATION_EXPORT NSString * const NSFileCreationDate;
FOUNDATION_EXPORT NSString * const NSFileOwnerAccountID;
FOUNDATION_EXPORT NSString * const NSFileGroupOwnerAccountID;
FOUNDATION_EXPORT NSString * const NSFileBusy;
FOUNDATION_EXPORT NSString * const NSFileProtectionKey NS_AVAILABLE_IOS(4_0);
FOUNDATION_EXPORT NSString * const NSFileProtectionNone NS_AVAILABLE_IOS(4_0);
FOUNDATION_EXPORT NSString * const NSFileProtectionComplete NS_AVAILABLE_IOS(4_0);
FOUNDATION_EXPORT NSString * const NSFileProtectionCompleteUnlessOpen NS_AVAILABLE_IOS(5_0);
FOUNDATION_EXPORT NSString * const NSFileProtectionCompleteUntilFirstUserAuthentication NS_AVAILABLE_IOS(5_0);

FOUNDATION_EXPORT NSString * const NSFileSystemSize;
FOUNDATION_EXPORT NSString * const NSFileSystemFreeSize;
FOUNDATION_EXPORT NSString * const NSFileSystemNodes;
FOUNDATION_EXPORT NSString * const NSFileSystemFreeNodes;

@interface NSDictionary (NSFileAttributes)

- (unsigned long long)fileSize;
- (NSDate *)fileModificationDate;
- (NSString *)fileType;
- (NSUInteger)filePosixPermissions;
- (NSString *)fileOwnerAccountName;
- (NSString *)fileGroupOwnerAccountName;
- (NSInteger)fileSystemNumber;
- (NSUInteger)fileSystemFileNumber;
- (BOOL)fileExtensionHidden;
- (OSType)fileHFSCreatorCode;
- (OSType)fileHFSTypeCode;
- (BOOL)fileIsImmutable;
- (BOOL)fileIsAppendOnly;
- (NSDate *)fileCreationDate;
- (NSNumber *)fileOwnerAccountID;
- (NSNumber *)fileGroupOwnerAccountID;
@end