Why is execSync not working in my code?

1
votes

I'm trying out various child process methods in nodejs. So to execute a linux command, I tried this code, where it prints the current working directory:

var execSync = require('child_process').execSync;

function commandOutput(error, stdout, stderr) {
    if (stderr !== null) {
        console.error(stderr);
    }
    if (error !== null) {
        console.error('execution error: ' + error);
    }
    if (stdout)console.log(stdout); 
    console.log("done");
}

var commandToExecute = "pwd";
execSync(commandToExecute, commandOutput);

console.log("executed");

While this works fine if I replace execSync with exec, the above code, i.e, with execSync gives the following error:

execSync(commandToExecute, commandOutput);
^
TypeError: undefined is not a function
    at Object. (/home/User_Name/fil.js:24:1)
    at Module._compile (module.js:456:26)
    at Object.Module._extensions..js (module.js:474:10)
    at Module.load (module.js:356:32)
    at Function.Module._load (module.js:312:12)
    at Function.Module.runMain (module.js:497:10)
    at startup (node.js:119:16)
    at node.js:902:3

Why is this happening? What should I change for this to work?

2
node.jsexecchild-process

2 Answers

0
votes

Try updating your Node to the latest stable version 6.10)

You can do that by running:

curl -sL https://deb.nodesource.com/setup_7.x | sudo -E bash -

sudo apt-get install -y nodejs

You can then check your version by running 

nodejs -v
0
votes

You are passing a callback to a sync function.
Try using exec instead of execSync. For further reference: https://nodejs.org/api/child_process.html#child_process_child_process_exec_command_options_callback