Node.js process.seteuid() Method

The process.seteuid() method is an inbuilt application programming interface of the process module which is used to set the effective user identity of the Node.js process.

Syntax:

process.seteuid( id )

Parameters: This method accepts single parameter as mentioned above and described below:  

• id: It is a required parameter that holds a String or an integer that denotes either numeric ID or username string. If username is passed, it blocks while resolving the associated numeric ID.

Return Value: It does not return any value.

Note: This function will only work on POSIX platforms. It is not available on windows or android platform so will cause an error i.e. TypeError, seteuid is not a function.

Below examples illustrate the use of process.seteuid() method in Node.js:

Example 1:

Javascript

// Node.js program to demonstrate the
// process.seteuid() method

// Include process module
const process = require('process');

// Printing the effective user identity
// of the Node.js process and checking
// whether the method exists or not
if (process.geteuid && process.seteuid ) {

  // Setting user id
  process.seteuid(400);

  // Printing geteuid()
  console.log("The effective user identity "
        + "of the Node.js process:"
        + process.geteuid());
}

Output:

The effective user identity of the Node.js process: 400

Example 2:

Javascript

// Node.js program to demonstrate the
// process.seteuid() method

// Include process module
const process = require('process');

// Setting user id and checking whether
// the method exists or not
if (process.seteuid) {

  // Within try catch
  try {
      process.seteuid(696);
      console.log("User id has successfully been set");
  } catch (err) {
      console.log("Failed to set user id:", err);
  }
}

// Checking whether the method exists or not
if (process.geteuid) {

    // Printing geteuid() value
    console.log("The numerical effective user "
          + "identity of the Node.js process:"
          + process.geteuid());
}

Output:

User id has successfully been set
The numerical effective user identity of the Node.js process: 696

Note: The above program will compile and run by using the node filename.js command.

Reference: https://nodejs.org/api/process.html#process_process_seteuid_id