# fs

Tests a user's permissions for the file or directory specified by path. The mode argument is an optional integer that specifies the accessibility checks to be performed. Check File access constants for possible values of mode. It is possible to create a mask consisting of the bitwise OR of two or more values (e.g. fs.constants.W_OK | fs.constants.R_OK).

Synchronously tests a user's permissions for the file or directory specified by path. The mode argument is an optional integer that specifies the accessibility checks to be performed. Check File access constants for possible values of mode. It is possible to create a mask consisting of the bitwise OR of two or more values (e.g. fs.constants.W_OK | fs.constants.R_OK).

Asynchronously append data to a file, creating the file if it does not yet exist. data can be a string or a buffer.Buffer.

Synchronously append data to a file, creating the file if it does not yet exist. data can be a string or a buffer.Buffer.

Asynchronously changes the permissions of a file. No arguments other than a possible exception are given to the completion callback.

This is a no-op on Titanium.

Synchronously changes the permissions of a file.

This is a no-op on Titanium.

Asynchronously changes owner and group of a file. No arguments other than a possible exception are given to the completion callback.

This is a no-op on Titanium.

Synchronously changes owner and group of a file.

This is a no-op on Titanium.

Asynchronous close. No arguments other than a possible exception are given to the completion callback.

Calling fs.close() on any file descriptor (fd) that is currently in use through any other fs operation may lead to undefined behavior.

Synchronous close.

Calling fs.close() on any file descriptor (fd) that is currently in use through any other fs operation may lead to undefined behavior.

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. Node.js makes no guarantees about the atomicity of the copy operation. If an error occurs after the destination file has been opened for writing, Node.js will attempt to remove the destination.

mode is an optional integer that specifies the behavior of the copy operation. It is possible to create a mask consisting of the bitwise OR of two or more values (e.g. fs.constants.COPYFILE_EXCL | fs.constants.COPYFILE_FICLONE).

• fs.constants.COPYFILE_EXCL: The copy operation will fail if dest already exists.
• fs.constants.COPYFILE_FICLONE: The copy operation will attempt to create a copy-on-write reflink. If the platform does not support copy-on-write, then a fallback copy mechanism is used.
• fs.constants.COPYFILE_FICLONE_FORCE: The copy operation will attempt to create a copy-on-write reflink. If the platform does not support copy-on-write, then the operation will fail.

Synchronously copies src to dest. By default, dest is overwritten if it already exists. Node.js makes no guarantees about the atomicity of the copy operation. If an error occurs after the destination file has been opened for writing, Node.js will attempt to remove the destination.

mode is an optional integer that specifies the behavior of the copy operation. It is possible to create a mask consisting of the bitwise OR of two or more values (e.g. fs.constants.COPYFILE_EXCL | fs.constants.COPYFILE_FICLONE).

• fs.constants.COPYFILE_EXCL: The copy operation will fail if dest already exists.
• fs.constants.COPYFILE_FICLONE: The copy operation will attempt to create a copy-on-write reflink. If the platform does not support copy-on-write, then a fallback copy mechanism is used.
• fs.constants.COPYFILE_FICLONE_FORCE: The copy operation will attempt to create a copy-on-write reflink. If the platform does not support copy-on-write, then the operation will fail.

Test whether or not the given path exists by checking with the file system.

Test whether or not the given path exists by checking with the file system.

Asynchronous fchmod.

This is a no-op on Titanium.

Synchronous fchmod.

This is a no-op on Titanium.

Asynchronous fchown.

This is a no-op on Titanium.

Synchronous fchown.

This is a no-op on Titanium.

Asynchronous fdatasync.

This is a no-op on Titanium.

Synchronous fdatasync.

This is a no-op on Titanium.

Asynchronous fstat. The callback gets two arguments (err, stats) where stats is an fs.Stats object. fstat() is identical to stat(), except that the file to be stat-ed is specified by the file descriptor fd.

Synchronous fstat.

Asynchronous lstat.

Synchronous lstat.

Asynchronously creates a directory.

The callback is given a possible exception and, if recursive is true, the first directory path created, (err, [path]).

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 directories should be created. Calling fs.mkdir() when path is a directory that exists results in an error only when recursive is false.

Synchronously creates a directory. Returns undefined, or if recursive istrue, the first directory path created. This is the synchronous version offs.mkdir()`.

Creates a unique temporary directory.

Generates six random characters to be appended behind a required prefix to create a unique temporary directory. Due to platform inconsistencies, avoid trailing X characters in prefix. Some platforms, notably the BSDs, can return more than six random characters, and replace trailing X characters in prefix with random characters.

The created directory path is passed as a string to the callback's second parameter.

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 detailed information, see the documentation of the asynchronous version of this API: mkdtemp.

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).

mode sets the file mode (permission and sticky bits), but only if the file was created. On Windows, only the write permission can be manipulated; see fs.chmod().

The callback gets two arguments (err, fd).

For detailed information, see the documentation of the asynchronous version of this API: fs.open().

Read data from the file specified by fd.

buffer is the buffer that the data (read from the fd) will be written to.

offset is the offset in the buffer to start writing at.

length is an integer specifying the number of bytes to read.

position is an argument specifying where to begin reading from in the file. 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.

The callback is given the three arguments, (err, bytesRead, buffer).

If the file is not modified concurrently, the end-of-file is reached when the number of bytes read is zero.

Asynchronous readdir. 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 '.' and '..'.

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.withFileTypes is set to true, the files array will contain fs.Dirent objects. NOTE: Titanium does not yet support this.

Synchronous readdir.

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 returned. If the encoding is set to 'buffer', the filenames returned will be passed as Buffer objects.

If options.withFileTypes is set to true, the result will contain fs.Dirent objects. Note: Titanium does not yet support this.

Asynchronously reads the entire contents of a file.

Synchronously reads the entire contents of a file.

For detailed information, see the documentation of the asynchronous version of this API: fs.read().

Asynchronously computes the canonical pathname by resolving ., .. and symbolic links.

A canonical pathname is not necessarily unique. Hard links and bind mounts can expose a file system entity through many pathnames.

Asynchronous realpath.

The callback gets two arguments (err, resolvedPath).

Only paths that can be converted to UTF8 strings are supported.

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 path passed to the callback. If the encoding is set to 'buffer', the path returned will be passed as a Buffer object.

Returns the resolved pathname.

For detailed information, see the documentation of the asynchronous version of this API: fs.realpath().

Synchronous realpath.

Only paths that can be converted to UTF8 strings are supported.

Asynchronously rename file at oldPath to the pathname provided as newPath. In the case that newPath already exists, it will be overwritten. If there is a directory at newPath, an error will be raised instead. No arguments other than a possible exception are given to the completion callback.

Synchronous rename. Returns undefined.

Asynchronous rmdir

Synchronously removes files and directories (modeled on the standard POSIX rm utility). Returns undefined.

Asynchronous stat. The callback gets two arguments (err, stats) where stats is an fs.Stats object.

In case of an error, the err.code will be one of Common System Errors.

Using fs.stat() to check for the existence of a file before calling fs.open(), fs.readFile() or fs.writeFile() is not recommended. Instead, user code should open/read/write the file directly and handle the error raised if the file is not available.

To check if a file exists without manipulating it afterwards, fs.access() is recommended.

Synchronous stat.

Asynchronous symlink which creates the link called path pointing to target. No arguments other than a possible exception are given to the completion callback.

This is a no-op on Titanium.

Synchronous symlink which creates the link called path pointing to target. No arguments other than a possible exception are given to the completion callback.

This is a no-op on Titanium.

Asynchronous truncate. Returns undefined. A file descriptor can also be passed as the first argument. In this case, fs.ftruncateSync() is called.

Synchronous truncate. Returns undefined. A file descriptor can also be passed as the first argument. In this case, fs.ftruncateSync() is called.

Asynchronous unlink. Returns undefined.

Synchronous unlink. Returns undefined.

Stop watching for changes on filename. If listener is specified, only that particular listener is removed. Otherwise, all listeners are removed, effectively stopping watching of filename.

This is a no-op on Titanium.

Change the file system timestamps of the object referenced by path.

This is a no-op on Titanium.

Change the file system timestamps of the object referenced by path.

This is a no-op on Titanium.

Watch for changes on filename, where filename is either a file or a directory.

This is a no-op on Titanium.

Watch for changes on filename. The callback listener will be called each time the file is accessed.

This is a no-op on Titanium.

For detailed information, see the documentation of the asynchronous version of this API.

When file is a filename, asynchronously writes data to the file, replacing the file if it already exists. data can be a string or a buffer.

When file is a file descriptor, the behavior is similar to calling fs.write() directly (which is recommended). See the notes below on using a file descriptor.

The encoding option is ignored if data is a buffer. If data is a normal object, it must have an own toString function property.

For detailed information, see the documentation of the asynchronous version of this API: fs.writeFile().

For detailed information, see the documentation of the asynchronous version of this API.