Node.js fs.openSync() Method

The fs.openSync() method is an inbuilt application programming interface of fs module which is used to return an integer value that represents the file descriptor. 

Syntax:

fs.openSync( path, flags, mode )

Parameters: This method accepts three parameters as mentioned above and described below:

• path: It holds the path of the file. It is of type string, Buffer, or URL.
• flags: It holds either a string or a number value. Its default value of it is 'r'.
• mode: It holds either a string or an integer value and its default value of it is 0o666.

Return Value: It returns a number that represents the file descriptor.

The below examples illustrate the use of the fs.openSync() method in Node.js:

Example 1: 

Output:

23

Here, the flag 'r' indicates that the file is already created and it reads the created file. 

Example 2: 

Output:

Program done!
closing file now

Here, the flag 'w' indicates that the file is created or overwritten. 

Reference: https://nodejs.org/api/fs.html#fs_fs_opensync_path_flags_mode