gistfile1.txt

var fork = require('fork').fork;
var netBinding = process.binding('net');
var net = require('net');
var ppid = process.pid;
var workers = [];
function preforkServer(port, numWorkers, clientServer)
{
    var srv = net.createServer(function(s) {
                s.pause();
                 var hv = 0;
                s.remoteAddress.split('.').forEach(function(v) {
                    hv += parseInt(v);
                });
                var i = hv % workers.length;
                workers[i].write('test', 'utf8', s.fd);
            }).listen(port);
    var spawnWorker = function(i)
    {
        var fds = netBinding.socketpair();

        var pid = fork();
        console.log('worker with pid ' + pid + ' spawned on i ' + i + ' from ' + process.pid);
        if(pid == 0)
        {

            var sr = new net.Stream(fds[0], 'unix');
            sr.resume();
            sr.on('end',function(){
                var index = workers.indexOf(sr);
                if(index >= 0)
                {
                    workers.splice(index, 1);
                }
            });
            workers.push(sr);
            return true;
        }else{

            var cl = new net.Stream(fds[1], 'unix');
            cl.resume();
            cl.on('fd', function(fd)
            {
                var client = new net.Stream(fd, 'unix');
                client.type = clientServer.type;
                client.server = clientServer;
                client.resume();

                clientServer.emit('connection', x);
            })
            cl.on('data', function(data){
                console.log('[client]', data);
            });
            return false;
        }
    }
    var i = 0;
    do
    {
        console.log('----------------');
        var ret = spawnWorker(i)
        console.log("ret from i " + i + " was ", ret);
    }while(ret && i++ < numWorkers);
}
var srv = require('http').createServer(function(req, resp) {
            resp.writeHead(200, {'Content-Type' : 'text/plain'});
            resp.write(ppid + ' (pid ' +pid + ')\n');
            resp.end();
        });
preforkServer(8124, 8, srv);
//process.openStdin();

gistfile2.txt

results to stdout:
>>> node fork.js
----------------
worker with pid 0 spawned on i 0 from 6866
ret from i 0 was  true
----------------
worker with pid 6867 spawned on i 0 from 6866
ret from i 0 was  false
worker with pid 0 spawned on i 1 from 6866
worker with pid 6868 spawned on i 1 from 6866
ret from i 1 was  true
----------------
ret from i 1 was  false
worker with pid 0 spawned on i 2 from 6866
ret from i 2 was  true
----------------
worker with pid 0 spawned on i 3 from 6866
worker with pid 6870 spawned on i 3 from 6866
ret from i 3 was  false
worker with pid 6869 spawned on i 2 from 6866
ret from i 2 was  false
ret from i 3 was  true
----------------
worker with pid 0 spawned on i 4 from 6866
ret from i 4 was  true
----------------
worker with pid 0 spawned on i 5 from 6866
ret from i 5 was  true
----------------
worker with pid 0 spawned on i 6 from 6866
ret from i 6 was  true
----------------
worker with pid 6871 spawned on i 4 from 6866
ret from i 4 was  false
worker with pid 0 spawned on i 7 from 6866
worker with pid 6872 spawned on i 5 from 6866
ret from i 7 was  true
----------------
ret from i 5 was  false
worker with pid 6873 spawned on i 6 from 6866
worker with pid 0 spawned on i 8 from 6866
ret from i 6 was  false
ret from i 8 was  true
worker with pid 6874 spawned on i 7 from 6866
ret from i 7 was  false
worker with pid 6875 spawned on i 8 from 6866
ret from i 8 was  false

gistfile3.txt

process tree:
>>> psf node
USER       PID %CPU %MEM    VSZ   RSS TTY      STAT START   TIME COMMAND
root      6709  1.0  0.2 645864  8964 pts/0    S+   16:09   0:00  |       \_ node fork.js
root      6710  0.1  0.1 645864  6268 pts/0    S+   16:09   0:00  |           \_ node fork.js
root      6711  0.1  0.1 645864  5424 pts/0    S+   16:09   0:00  |               \_ node fork.js
root      6712  0.0  0.1 645864  5376 pts/0    S+   16:09   0:00  |                   \_ node fork.js
root      6713  0.0  0.1 645864  5376 pts/0    S+   16:09   0:00  |                       \_ node fork.js
root      6714  0.1  0.1 645864  5376 pts/0    S+   16:09   0:00  |                           \_ node fork.js
root      6715  0.0  0.1 645864  5376 pts/0    S+   16:09   0:00  |                               \_ node fork.js
root      6716  0.0  0.1 645864  5384 pts/0    S+   16:09   0:00  |                                   \_ node fork.js
root      6717  0.0  0.1 645864  5384 pts/0    S+   16:09   0:00  |                                       \_ node fork.js
root      6718  0.0  0.1 645864  5328 pts/0    S+   16:09   0:00  |                                           \_ node fork.js