How to get the cwd (current working directory) from a nodejs child process (in both windows and linuxish)

Question

I'm trying to run a script via nodejs that does:

cd .. doSomethingThere[] 

However, to do this, I need to executed multiple child processes and carry over the environment state between those processes. What i'd like to do is:

var exec = require('child_process').exec; var child1 = exec('cd ..', function (error, stdout, stderr) {   var child2 = exec('cd ..', child1.environment, function (error, stdout, stderr) {   }); }); 

or at very least:

var exec = require('child_process').exec; var child1 = exec('cd ..', function (error, stdout, stderr) {   var child2 = exec('cd ..', {cwd: child1.process.cwd()}, function (error, stdout, stderr) {   }); }); 

How can I do this?

Answer 1

to start child with parent dir as cwd:

var exec = require('child_process').exec; var path = require('path')  var parentDir = path.resolve(process.cwd(), '..'); exec('doSomethingThere', {cwd: parentDir}, function (error, stdout, stderr) {   // if you also want to change current process working directory:   process.chdir(parentDir); }); 

Update: if you want to retrieve child's cwd:

var fs = require('fs'); var os = require('os'); var exec = require('child_process').exec;  function getCWD(pid, callback) {   switch (os.type()) {   case 'Linux':     fs.readlink('/proc/' + pid + '/cwd', callback); break;   case 'Darwin':     exec('lsof -a -d cwd -p ' + pid + ' | tail -1 | awk \'{print $9}\'', callback);     break;   default:     callback('unsupported OS');   } }  // start your child process //    note that you can't do like this, as you launch shell process  //    and shell's child don't change it's cwd: // var child1 = exec('cd .. & sleep 1 && cd .. sleep 1'); var child1 = exec('some process that changes cwd using chdir syscall');  // watch it changing cwd: var i = setInterval(getCWD.bind(null, child1.pid, console.log), 100); child1.on('exit', clearInterval.bind(null, i));      

Answer 2

If you want to get the current working directory without resorting to OS specific command line utilities, you can use the "battled-tested" shelljs library that abstract these things for you, while underneath using child processes.

var sh = require("shelljs"); var cwd = sh.pwd(); 

There you have it, the variable cwd holds your current working directory whether you're on Linux, Windows, or freebsd.