Close a file descriptor.
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> Close a file descriptor.
``bash`
npm install @stdlib/fs-close
`javascript`
var close = require( '@stdlib/fs-close' );
#### close( fd, clbk )
Asynchronously closes a file descriptor, so that the file descriptor no longer refers to any file and may be reused.
`javascript
var openSync = require( '@stdlib/fs-open' ).sync;
var fd = openSync( __filename );
close( fd, done );
function done( error ) {
if ( error ) {
throw error;
}
}
`
#### close.sync( fd )
Synchronously closes a file descriptor.
`javascript
var openSync = require( '@stdlib/fs-open' ).sync;
var fd = openSync( __filename );
var err = close.sync( fd );
if ( err instanceof Error ) {
throw err;
}
`
- The difference between this API and [fs.closeSync()][node-fs] is that [fs.closeSync()][node-fs] will throw if an error is encountered (e.g., if given an invalid file descriptor) and this API will return an error.
`javascript
var join = require( 'path' ).join;
var openSync = require( '@stdlib/fs-open' ).sync;
var close = require( '@stdlib/fs-close' );
var err;
/ Sync /
var fd = openSync( join( __dirname, 'package.json' ), 'r+' );
if ( fd instanceof Error ) {
console.error( fd.message );
} else {
err = close.sync( fd );
// returns undefined
if ( err instanceof Error ) {
console.error( err.message );
} else {
console.log( 'Synchronously closed file descriptor.' );
}
}
/ Async /
fd = openSync( join( __dirname, 'package.json' ), 'r+' );
if ( fd instanceof Error ) {
console.error( fd.message );
} else {
close( fd, done );
}
function done( error ) {
if ( error ) {
console.error( error.message );
} else {
console.log( 'Asynchronously closed file descriptor.' );
}
}
`
*
- [@stdlib/fs-exists][@stdlib/fs/exists]: test whether a path exists on the filesystem.
- [@stdlib/fs-open][@stdlib/fs/open]: open a file.
- [@stdlib/fs-read-file][@stdlib/fs/read-file]: read the entire contents of a file.
*
This package is part of [stdlib][stdlib], a standard library for JavaScript and Node.js, with an emphasis on numerical and scientific computing. The library provides a collection of robust, high performance libraries for mathematics, statistics, streams, utilities, and more.
For more information on the project, filing bug reports and feature requests, and guidance on how to develop [stdlib][stdlib], see the main project [repository][stdlib].
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---
See [LICENSE][stdlib-license].
Copyright © 2016-2026. The Stdlib [Authors][stdlib-authors].
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