No arguments other than a possible exception are given to the completion callback. The mode argument used in both the fs. An easier method of constructing the mode is to use a sequence of three octal digits e. The left-most digit 7 in the example , specifies the permissions for the file owner.
The middle digit 6 in the example , specifies permissions for the group. The right-most digit 5 in the example , specifies the permissions for others.
When using raw numbers where file modes are expected, any value larger than 0o may result in platform-specific behaviors that are not supported to work consistently. Caveats: on Windows only the write permission can be changed, and the distinction among the permissions of group, owner or others is not implemented.
For detailed information, see the documentation of the asynchronous version of this API: fs. Asynchronously changes owner and group of a file. Synchronously changes owner and group of a file. Returns undefined. This is the synchronous version of fs. Asynchronous close 2. Synchronous close 2. Returns an object containing commonly used constants for file system operations.
The specific constants currently defined are described in FS Constants. Asynchronously copies src to dest. By default, dest is overwritten if it already exists. No arguments other than a possible exception are given to the callback function. If an error occurs after the destination file has been opened for writing, Node.
Synchronously copies src to dest. Unlike the 16 kb default highWaterMark for a readable stream, the stream returned by this method has a default highWaterMark of 64 kb.
Both start and end are inclusive and start counting at 0. If fd is specified and start is omitted or undefined , fs. The encoding can be any one of those accepted by Buffer. If fd is specified, ReadStream will ignore the path argument and will use the specified file descriptor. This means that no 'open' event will be emitted. If fd points to a character device that only supports blocking reads such as keyboard or sound card , read operations do not finish until data is available. This can prevent the process from exiting and the stream from closing naturally.
If autoClose is false, then the file descriptor won't be closed, even if there's an error.
It is the application's responsibility to close it and make sure there's no file descriptor leak. If autoClose is set to true default behavior , on 'error' or 'end' the file descriptor will be closed automatically. If autoClose is set to true default behavior on 'error' or 'finish' the file descriptor will be closed automatically.
Like ReadStream , if fd is specified, WriteStream will ignore the path argument and will use the specified file descriptor. Test whether or not the given path exists by checking with the file system.
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Then call the callback argument with either true or false:. The parameters for this callback are not consistent with other Node. Normally, the first parameter to a Node. This is one reason fs. The "not recommended" examples above check for existence and then use the file; the "recommended" examples are better because they use the file directly and handle the error, if any.
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The callback parameter to fs. Asynchronous fchmod 2. Synchronous fchmod 2. Asynchronous fchown 2. Synchronous fchown 2. Asynchronous fdatasync 2. Synchronous fdatasync 2. Accepts an additional options object to specify whether the numeric values returned should be bigint. Asynchronous fstat 2. The callback gets two arguments err, stats where stats is an fs.
Stats object. Synchronous fstat 2. Asynchronous fsync 2. Synchronous fsync 2. Asynchronous ftruncate 2. If the file referred to by the file descriptor was larger than len bytes, only the first len bytes will be retained in the file. Change the file system timestamps of the object referenced by the supplied file descriptor. See fs. This function does not work on AIX versions before 7. Synchronous version of fs. Asynchronous lchmod 2. Synchronous lchmod 2. Asynchronous lchown 2.
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Synchronous lchown 2. Asynchronous link 2. Synchronous link 2. Asynchronous lstat 2. The callback gets two arguments err, stats where stats is a fs. Synchronous lstat 2. The second argument can now be an options object with recursive and mode properties. Asynchronously creates a directory.
The optional options argument can be an integer specifying mode permission and sticky bits , or an object with a mode property and a recursive property indicating whether parent folders should be created. On Windows, using fs. Synchronously creates a directory. Generates six random characters to be appended behind a required prefix to create a unique temporary directory.
The optional options argument can be a string specifying an encoding, or an object with an encoding property specifying the character encoding to use. Asynchronous file open. See open 2. On Windows, only the write permission can be manipulated; see fs. Functions based on fs.
The buffer parameter can now be any TypedArray , or a DataView. If position is null , data will be read from the current file position, and the file position will be updated. If position is an integer, the file position will remain unchanged. If this method is invoked as its util. Asynchronous readdir 3. Reads the contents of a directory. The callback gets two arguments err, files where files is an array of the names of the files in the directory excluding '. The optional options argument can be a string specifying an encoding, or an object with an encoding property specifying the character encoding to use for the filenames passed to the callback.
If the encoding is set to 'buffer' , the filenames returned will be passed as Buffer objects. If options. Dirent objects. Synchronous readdir 3.
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