linux - Daemonize 'child_process' that was 'fork'ed -


i trying achieve behavior similar 1 httpd has when starting nodejs. when say:

service httpd start

in ps, we'll see:

[root@dev ~]# service httpd start starting httpd:                                            [  ok  ] [root@dev ~]# ps auxf | grep httpd root      3395  0.0  0.1   6336   304 pts/0    r+   12:03   0:00  |       \_ grep httpd root      3391  0.0  1.3 175216  3656 ?        ss   12:02   0:00 /usr/sbin/httpd apache    3393  0.0  0.9 175216  2432 ?        s    12:02   0:00  \_ /usr/sbin/httpd

notice how httpd master , child have no terminal (? shown instead of pts/0 grep).

now... need ipc channel , therefore use child_process.fork no matter do, every time see terminal still attached daemon. here code welcome experiment on:

c.js - controller

var cp = require('child_process');  var d = cp.fork('d.js', {});  d.on('message', function() {   d.disconnect();   d.unref(); });

d.js - daemon

process.send('ready');  settimeout(function() {   console.log('test'); }, 10000);

and see in terminal:

[root@dev ~]# node c.js                 # running control script [root@dev ~]# ps auxf | grep node       # terminal interactive again check root      3472  0.0  0.3 103308   864 pts/0    s+   12:13   0:00  |       \_ grep node root      3466  1.1  5.6 648548 14904 pts/0    sl   12:13   0:00 /usr/bin/node d.js [root@dev ~]# test                      # appears outta because d.js still has stdout

d.js still has pts/0 , writes test when it's interactive bash me.

how fix , make daemon drop terminal? don't care side (c.js or d.js) gets adjustments code, control both, need ipc channel , therefore has done via fork.

this can solved ditching fork in favor of spawn. same code can rewritten to:

var cp = require('child_process'); var d = cp.spawn(process.execpath, ['./d.js'], {   detached: true,   stdio: ['ignore', 'ignore', 'ignore', 'ipc'] });  d.unref(); d.disconnect();

the stdio part how fork works internally. have no idea why decided not expose full array , instead gave silent.

d.js have no terminal right @ start (it /dev/null - same httpd). not tested on windows.


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