Web/API/FileSystemFlags/exclusive

This is an experimental technologyCheck the Browser compatibility table carefully before using this in production.

The exclusive property on the FileSystemFlags dictionary is used in tandem with the create property to determine whether or not it's acceptable to require that the file not already exist when the reference to it is created by calling FileSystemDirectoryEntry.getFile() or FileSystemDirectoryEntry.getDirectory().

Syntax

fileSystemFlags.exclusive = booleanValue

Values

The table below describes the result of each possible combination of these flags depending on whether or not the target file or directory path already exists.

Option values		File/directory condition	Result
`create`			`exclusive`
`false`	n/a^[1]	Path exists and matches the desired type (depending on whether the function called is `getFile()` or `getDirectory()`	The `successCallback` is called with a `FileSystemFileEntry` if `getFile()` was called or a `FileSystemDirectoryEntry` if `getDirectory()` was called.
`false`	n/a^[1]	Path exists but doesn't match the desired type	The `errorCallback` is called with an appropriate error code (if the callback was provided).
`true`	`false`	Path exists	The existing file or directory is removed and replaced with a new one, then the `successCallback` is called with a `FileSystemFileEntry` or a `FileSystemDirectoryEntry`, as appropriate.
`true`	`false`	Path doesn't exist	The file or directory is created, then a `FileSystemFileEntry` or a `FileSystemDirectoryEntry` is passed to the `successCallback`, as appropriate.
`true`	`true`	Path exists	The `errorCallback` is called with an appropriate error, such as `FileError.PATH_EXISTS_ERR`.
`true`	`true`	Path doesn't exist	The file or directory is created, then a `FileSystemFileEntry` or a `FileSystemDirectoryEntry` is passed to the `successCallback`, as appropriate.

[1] When create is false, the value of exclusive is irrelevant and ignored.

Specifications

Specification	Status	Comment
File and Directory Entries APIThe definition of 'FileSystemFlags' in that specification.	Draft	Initial specification.

Browser compatibility

Update compatibility data on GitHub

	Desktop						Mobile
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet
`exclusive` Experimental'	Chrome Full support 13 Prefixed' Full support 13 Prefixed' Prefixed' Implemented with the vendor prefix: webkit	Edge Full support ≤79 Prefixed' Full support ≤79 Prefixed' Prefixed' Implemented with the vendor prefix: webkit	Firefox Partial support 50 Notes' Partial support 50 Notes' Notes' For security reasons, Firefox does not support creating files. This option has no effect.	IE No support No	Opera No support No	Safari No support No	WebView Android Full support Yes Prefixed' Full support Yes Prefixed' Prefixed' Implemented with the vendor prefix: webkit	Chrome Android Full support Yes Prefixed' Full support Yes Prefixed' Prefixed' Implemented with the vendor prefix: webkit	Firefox Android Partial support 50 Notes' Partial support 50 Notes' Notes' For security reasons, Firefox does not support creating files. This option has no effect.	Opera Android No support No	Safari iOS No support No	Samsung Internet Android Full support Yes Prefixed' Full support Yes Prefixed' Prefixed' Implemented with the vendor prefix: webkit

Legend

Full support: Full support
Partial support: Partial support
No support: No support
Experimental. Expect behavior to change in the future.': Experimental. Expect behavior to change in the future.
See implementation notes.': See implementation notes.
Requires a vendor prefix or different name for use.': Requires a vendor prefix or different name for use.