Question

56

nodeJS child_process.spawn does not work when one of the args has a space in it

rated 0 times [ 63] [ 7] / answers: 1 / hits: 25363 / 12 Years ago, fri, june 8, 2012, 12:00:00

I am trying to use the child_process.spawn function. The syntax is

child_process.spawn(command, args=[], [options])

Whenever I include a space in any of the elements of the args array, the command simply emits the argument. Here is some code I used to test it

var spawn = require(child_process).spawn



console.log(This works);

var watcher = spawn(ls, [-l]);

watcher.stdout.on('data', function(data) {

    process.stdout.write(data.toString());

});



console.log(This does not work);

watcher = spawn(ls, [-l, /path with space in it]);

watcher.stdout.on('data', function(data) {

    process.stdout.write(data.toString());

});

Is this a bug in node? Do I need to escape the space?

Edit: The above code is just an example. Here is the real code.
Maybe is has to do with the pipes?

watcher = spawn(supervisor, [--extensions 'coffee|js|css|coffeekup', src/app.coffee]);

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alyssiat

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4 Years ago

answered 12 Years ago wilson · Accepted Answer

Don't put spaces in args, just use another argument in the array

var watcher = spawn(supervisor, [

  --extensions,

  'coffee|js|css|coffeekup',

  src/app.coffee

]);

A handy little shortcut I found if you want to get quick diagnostic output from your child processes is passing the {stdio: inherit} in options

var watcher = spawn(supervisor, [

  --extensions,

  'coffee|js|css|coffeekup',

  src/app.coffee

], {stdio: inherit});

This way you can see whether everything is working properly right away.

Lastly, depending on where supervisor is installed, you might want to consider using the full path.

var watcher = spawn(/path/to/supervisor, ...);