node 4.1.2 on OS X: child_process emits exit/close to wrong instance

[minesworld]

node --version => v4.1.2
uname -a => Darwin xxx 15.0.0 Darwin Kernel Version 15.0.0: Wed Aug 26 16:57:32 PDT 2015; root:xnu-3247.1.106~1/RELEASE_X86_64 x86_64

only the last spawned child_process instance will get the emitted 'exit' and 'close' events, but this also for OTHER instances too...

100% reproducable with this source:

var child_process = require('child_process');

ChildProcess = function(description, executable, arguments, callback) {
  this.description = description;
  this.exited = false;

  this.process = child_process.spawn(executable, arguments);

  self = this;

  this.process.on('exit', function(code, signal) {

    self.exited = true;
    console.log(self.description + " process.on:exit", code, signal);

  }).on('close', function(code, signal) {

    self.exited = true;
    console.log(self.description + " process.on:close", code, signal);

    if (callback) callback(code, signal);

  }).on('error', function(err) {

    console.log(self.description + " process.on:error", err);

  });
}

ChildProcess.prototype.kill = function(signal) {
  if (this.exited) return;

  console.log(this.description + " .kill", signal);

  this.process.kill(signal);
}


p1 = new ChildProcess("p1", "/bin/sleep", [ "11" ], function(code, signal) {
  console.log("p1 <= ", code, signal);
});

p2 = new ChildProcess("p2", "/bin/sleep", [ "12" ], function(code, signal) {
  console.log("p2 <= ", code, signal);
});

setTimeout(function() {
  p2.kill("SIGTERM");
  p1.kill("SIGTERM");
}, 1000);

Output is

p2 .kill SIGTERM
p1 .kill SIGTERM
p2 process.on:exit null SIGTERM
p2 process.on:exit null SIGTERM
p2 process.on:close null SIGTERM
p2 <=  null SIGTERM
p2 process.on:close null SIGTERM
p1 <=  null SIGTERM

[evanlucas]

Hm, I cannot reproduce. I have this:

'use strict'

const spawn = require('child_process').spawn

function ChildProcess(desc, exe, args, cb) {
  this.desc = desc
  this.exited = false
  var self = this

  this.process = spawn(exe, args)
    .on('exit', function(code, signal) {
      self.exited = true
      console.log(self.desc, 'exit', code, signal)
    })
    .on('close', function(code, signal) {
      self.exited = true
      console.log(self.desc, 'close', code, signal)
      if (cb) cb(code, signal)
    })
    .on('error', function(err) {
      console.log(self.desc, 'error', err)
    })
}

ChildProcess.prototype.kill = function(signal) {
  if (this.exited)
    return

  console.log(this.desc, 'kill', signal)
  this.process.kill(signal)
}

var p1 = new ChildProcess('p1', '/bin/sleep', ['11'], function(code, signal) {
  console.log('p1 <=', code, signal)
})

var p2 = new ChildProcess('p2', '/bin/sleep', ['12'], function(code, signal) {
  console.log('p2 <=', code, signal)
})

setTimeout(function() {
  p2.kill('SIGTERM')
  p1.kill('SIGTERM')
}, 1000)

It looks like you have some global variables in that code, which could be causing an issue?

[evanlucas]

With the above, I get the following output:

p2 kill SIGTERM
p1 kill SIGTERM
p1 exit null SIGTERM
p2 exit null SIGTERM
p1 close null SIGTERM
p1 <= null SIGTERM
p2 close null SIGTERM
p2 <= null SIGTERM

[minesworld]

My fault. ( var self = this ) ...

[minesworld]

You’re right.

Thanks a thousand times for the ‘use strict’ info…

Shame about me…

Michael

On 07 Oct 2015, at 15:34, Evan Lucas notifications@github.com wrote:

With the above, I get the following output:

p2 kill SIGTERM
p1 kill SIGTERM
p1 exit null SIGTERM
p2 exit null SIGTERM
p1 close null SIGTERM
p1 <= null SIGTERM
p2 close null SIGTERM
p2 <= null SIGTERM

—
Reply to this email directly or view it on GitHub.