The method takes as an argument an NSString object containing the path to file and returns a boolean YES or NO value indicating the presence or otherwise of that file:. The contents of two files can be compared for equality using the contentsEqualAtPath method. This method takes as arguments the paths to the two files to be compared and returns a boolean YES or NO to indicate whether the file contents match:. Most operating systems provide some level of file access control.
These typically take the form of attributes that control the level of access to a file for each user or user group. As such, it is not a certainty that your program will have read or write access to a particular file, or the appropriate permissions to delete or execute it. Each method takes a single argument in the form of the path to the file to be checked and returns a boolean YES or NO result. For example, the following code excerpt checks to find out if a file is writable:.
To check for other access permissions simply substitute the corresponding method name in place of isWritableFileAtPath in the above example. This method returns a boolean YES or NO result and takes as arguments the pathname for the file to be moved, the destination path and an optional NSError object into which information describing any errors encountered during the operation will be placed.
If no error description information is required, this argument may be set to NULL. Note that if the destination file path already exists this operation will fail. File copying can be achieved using the copyItemAtPath method.
As with the move method, this takes as arguments the source and destination pathnames and an optional NSError object. Success of the operation is indicated by the returned boolean value:. The removeItemAtPath method removes the specified file from the file system. The method takes as arguments the pathname of the file to be removed and an optional NSError object.
The success of the operation is, as usual, reported in the form of a boolean YES or NO return value:. A symbolic link to a particular file may be created using the createSymbolicLinkAtPath method. This takes as arguments the path of the symbolic link, the path to the file to which the link is to refer and an optional NSError object. The NSFileManager class includes some basic file reading and writing capabilities.
Firstly, the contents of a file may be read and stored in an NSData object through the use of the contentsAtPath method:. Having stored the contents of a file in an NSData object, that data may subsequently be written out to a new file using the createFileAtPath method:.
Connect and share knowledge within a single location that is structured and easy to search. I would like to download files directly from an URL to the disk using objective-c on the iPhone os. How can I change the download handling still having the request beeing synchronous, it is already in a background thread to write the data directly to disk, not using memory variables to store the complete content only small parts?
Also, there's not a lot of error handling. Caveat Implementor. The basic idea is that you create a standard NSURLConnection , which is normally asynchronous, but just block the thread by spinning the runloop yourself until the connection is done. You also use a custom url connection delegate to just pipe any data the connection receives directly to a file.
Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams? Collectives on Stack Overflow. Learn more. How to download files directly to disk on the iPhone os?
Ask Question. Asked 11 years, 6 months ago. Active 11 years, 6 months ago. Viewed 8k times. A sample code would be appreciated. If it doesn't then JGDownloadAcceleration will simply use 1 connection to download the content conventionally. An easy to understand explanation of the Python License 2. Skip to content. Star Branches Tags. Could not load branches. Could not load tags. Latest commit. Git stats commits. Failed to load latest commit information. JGDownloadAcceleration Classes. JGDownloadAcceleration Tester.
View code. How does the download acceleration even work? More info: Wikipedia Current Version: 1. Overview JGDownloadAcceleration consists of 2 different classes that are available to use for networking. About Download acceleration for iOS.
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