It&#39;s built into node and called [`os.cpus()`](http://nodejs.org/api/os.html#os_os_cpus)

&gt; Returns an array of objects containing information about each CPU/core installed: model, speed (in MHz), and times (an object containing the number of milliseconds the CPU/core spent in: user, nice, sys, idle, and irq). 

The length of this array is the number of &quot;processors&quot; in the system. Most systems only have one CPU, so that&#39;s the number of cores of that CPU.

See the code below:
```
const os = require(&#39;os&#39;)
const cpuCount = os.cpus().length
```

    var os = require(&#39;os&#39;),
    cpuCount = os.cpus().length;

In your CLI you can run the following log the # of cores on the machine.

    node -e &#39;console.log(require(&quot;os&quot;).cpus().length)&#39;

I have two files `main.go` which is under `package main`, and another file with some functions in the package called functions.

My question is: How can I call a function from `package main`?

**File 1: main.go (located in MyProj/main.go)**

    package main

    import &quot;fmt&quot;
    import &quot;functions&quot; // I dont have problem creating the reference here

    func main(){
        c:= functions.getValue() // &lt;---- this is I want to do
    }

**File 2: functions.go (located in MyProj/functions/functions.go)**

    package functions

    func getValue() string{
        return &quot;Hello from this another package&quot;
    }


Call a function from another package in Go

I&#39;m building a small CMS in Laravel and I tried to show the content (which is stored in the DB). It is showing the HTML tags instead of executing them. Its like there is an auto html_entity_decode for all printed data.

&lt;!-- language: php --&gt;

    &lt;?php

    class CmsController extends BaseController
    {
        public function Content($name)
        {    
            $data = Pages::where(&#39;CID&#39;, &#39;=&#39;, Config::get(&#39;company.CID&#39;))
                -&gt;where(&#39;page_name&#39;, &#39;=&#39;, $name)
                -&gt;first();

            return View::make(&#39;cms.page&#39;)-&gt;with(&#39;content&#39;, $data);
        }
    }


I tried to print the content using the curly brace.

&lt;!-- language: php --&gt;

    {{ $content-&gt;page_desc }}

and triple curly brace.

&lt;!-- language: php --&gt;

    {{{ $content-&gt;page_desc }}}

And they give the same result. I need to execute those HTML tags instead of escaping them.

Laravel Escaping All HTML in Blade Template

This is really just to satisfy curiosity, and see if there&#39;s a better way to do this.

On my Windows 8 box, Node&#39;s `process.env` object has a `NUMBER_OF_PROCESSORS` property, on my Linux box it doesn&#39;t.

Obviously different platforms have different environment variables, that much is a given, but it seems like NUMBER_OF_PROCESSORS would be a useful thing to have regardless.

My quick fix for Linux was spawning a child process to run the `nproc` command, but I&#39;d like to avoid using a callback for simply getting the number of processors. Seems like there must be a simpler way.

What have other people done to solve this?

Node.js - Get number of processors available

This is really just to satisfy curiosity, and see if there's a better way to do this.
On my Windows 8 box, Node's <code>process.env</code> object has a <code>NUMBER_OF_PROCESSORS</code> property, on my Linux box it doesn't.
Obviously different platforms have different environment variables, that much is a given, but it seems like NUMBER_OF_PROCESSORS would be a useful thing to have regardless.
My quick fix for Linux was spawning a child process to run the <code>nproc</code> command, but I'd like to avoid using a callback for simply getting the number of processors. Seems like there must be a simpler way.
What have other people done to solve this?

I try to kill a process by pid file:

    kill -9 $(cat /var/run/myProcess.pid)

The pid file contains the process number. However executing the kill gives me no stdout and the processes is still alive. But this works:

    kill -9 PID

What is wrong with the first kill command? Does it fail to extract the PID from the file?

Example content of pid file:

    5424

and 

    kill -9 5424

works.

Kill process by pid file

I had to run `jmap` in order to take heap dump of my process. but `jvm` returned:

    Unable to open socket file: target process not responding or HotSpot VM not loaded
    The -F option can be used when the target process is not responding

So I used the `-F`:

    ./jmap -F -dump:format=b,file=heap.bin 10330
    Attaching to process ID 10331, please wait...
    Debugger attached successfully.
    Server compiler detected.
    JVM version is 24.51-b03
    Dumping heap to heap.bin ...

1. Using `-F`  is allright  for taking heap dump?
2. I am waiting 20 minutes and not finished yet. Any ideas why?

Running jmap getting Unable to open socket file


I am supposed to set the EC2_HOME and JAVA_HOME variables
before running a command (ec2-describe-regions)

How do I do that in one go?


How set multiple env variables for a bash command

I just installed python 2.7 and also pip to the 2.7 site package.

When I get the version with:

    pip -V

It shows:

    pip 1.3.1 from /usr/lib/python2.6/site-packages (python 2.6)

How do I use the 2.7 version of pip located at: 

    /usr/local/lib/python2.7/site-packages

how to use python2.7 pip instead of default pip

When I run `mongo`, I get the warning:

&gt; Failed global initialization: BadValue Invalid or no user locale set. Please ensure LANG and/or LC_* environment variables are set correctly.

BadValue Invalid or no user locale set. Please ensure LANG and/or LC_* environment variables are set correctly

Node.js script won&#39;t exit if there&#39;s callbacks left in the main event loop. While one could forcefully terminate the script by calling `process.exit()` or throwing exceptions, it is recommended to let the script terminate &quot;naturally&quot;, by always doing proper cleanup. However, this sometimes can be difficult as bugs in the code may prevent proper cleanup, e.g., I may forget to remove an IntervalObject when no longer needed, etc., which eventually prevents the program from terminating.

Therefore, is there a way to debug a non-terminating script to find out what&#39;s remaining registered in the event loop? In other words, is there a way in Node.js to debug what&#39;s preventing the program from exiting?

Node.js: inspect what&#39;s left in the event loop that&#39;s preventing the script from exiting naturally

I am playing around with Nodejs and express by building a small rest API. My question is, what is the good practice/best way to set the code status, as well as the response data?

Let me explain with a little bit of code (I will not put the node and express code necessary to start the server, just the router methods that are concerned):

    router.get(&#39;/users/:id&#39;, function(req, res, next) {
      var user = users.getUserById(req.params.id);
      res.json(user);
    });


    exports.getUserById = function(id) {
      for (var i = 0; i &lt; users.length; i++) {
        if (users[i].id == id) return users[i];
      }
    };

The code below works perfectly, and when sending a request with Postman, I get the following result:
![enter image description here][1]

As you can see, the status shows 200, which is OK. But is this the best way to do this? Is there a case where I should have to set the status myself, as well as the returned JSON? Or is that always handled by express?

For example, I just made a quick test and slightly modified the get method above:

    router.get(&#39;/users/:id&#39;, function(req, res, next) {
      var user = users.getUserById(req.params.id);
      if (user == null || user == &#39;undefined&#39;) {
        res.status(404);
      }
      res.json(user);
    });

As you can see, if the user is not found in the array, I will just set a status of 404.

Resources/advices to learn more about this topic are more than welcome.


  [1]: http://i.stack.imgur.com/0EMs8.png

Proper way to set response status and JSON content in a REST API made with nodejs and express

I am still fairly new to promises and am using bluebird currently, however I have a scenario where I am not quite sure how to best deal with it.

So for example I have a promise chain within an express app like so:

    repository.Query(getAccountByIdQuery)
    		.catch(function(error){
    			res.status(404).send({ error: &quot;No account found with this Id&quot; });
    		})
    		.then(convertDocumentToModel)
    		.then(verifyOldPassword)
    		.catch(function(error) {
    			res.status(406).send({ OldPassword: error });
    		})
    		.then(changePassword)
    		.then(function(){
    			res.status(200).send();
    		})
    		.catch(function(error){
    			console.log(error);
    			res.status(500).send({ error: &quot;Unable to change password&quot; });
    		});

So the behaviour I am after is:

- Goes to get account by Id
- If there is a rejection at this point, bomb out and return an error
- If there is no error convert the document returned to a model
- Verify the password with the database document
- If the passwords dont match then bomb out and return a different error
- If there is no error change the passwords
- Then return success
- If anything else went wrong, return a 500

So currently catches do not seem to stop the chaining, and that makes sense, so I am wondering if there is a way for me to somehow force the chain to stop at a certain point based upon the errors, or if there is a better way to structure this to get some form of branching behaviour, as there is a case of `if X do Y else Z`.

Any help would be great.

Handling multiple catches in promise chain

[add]
So my next problem is that when i try adding a new dependence (npm install --save socket.io). The JSON file is also valid. I get this error:
Failed to parse json

    npm ERR! Unexpected string
    npm ERR! File: /Users/John/package.json
    npm ERR! Failed to parse package.json data.
    npm ERR! package.json must be actual JSON, not just JavaScript.
    npm ERR! 
    npm ERR! This is not a bug in npm.
    npm ERR! Tell the package author to fix their package.json file. JSON.parse 


So I&#39;ve been trying to figure out why this error has been returning. All of the files (HTML,JSON,JS) are inside the same folder on my desktop. I&#39;m using node.js and socket.io

This is my JS file:

    var app = require(&#39;express&#39;)();
    var http = require(&#39;http&#39;).Server(app);
    
    app.get(&#39;/&#39;, function(req, res){
      res.sendFile(&#39;index.html&#39;);
    });
    
    http.listen(3000,function(){
    	console.log(&#39;listening on : 3000&#39;);
    });

This is what is getting returned:

    MacBook-Pro:~ John$ node /Users/John/Desktop/Chatapp/index.js 
    listening on : 3000
    TypeError: path must be absolute or specify root to res.sendFile
        at ServerResponse.sendFile (/Users/John/node_modules/express/lib/response.js:389:11)
        at /Users/John/Desktop/Chatapp/index.js:5:7
        at Layer.handle [as handle_request] (/Users/John/node_modules/express/lib/router/layer.js:76:5)
        at next (/Users/John/node_modules/express/lib/router/route.js:100:13)
        at Route.dispatch (/Users/John/node_modules/express/lib/router/route.js:81:3)
        at Layer.handle [as handle_request] (/Users/John/node_modules/express/lib/router/layer.js:76:5)
        at /Users/John/node_modules/express/lib/router/index.js:234:24
        at Function.proto.process_params (/Users/John/node_modules/express/lib/router/index.js:312:12)
        at /Users/John/node_modules/express/lib/router/index.js:228:12
        at Function.match_layer (/Users/John/node_modules/express/lib/router/index.js:295:3)
    TypeError: path must be absolute or specify root to res.sendFile
        at ServerResponse.sendFile (/Users/John/node_modules/express/lib/response.js:389:11)
        at /Users/John/Desktop/Chatapp/index.js:5:7
        at Layer.handle [as handle_request] (/Users/John/node_modules/express/lib/router/layer.js:76:5)
        at next (/Users/John/node_modules/express/lib/router/route.js:100:13)
        at Route.dispatch (/Users/John/node_modules/express/lib/router/route.js:81:3)
        at Layer.handle [as handle_request] (/Users/John/node_modules/express/lib/router/layer.js:76:5)
        at /Users/John/node_modules/express/lib/router/index.js:234:24
        at Function.proto.process_params (/Users/John/node_modules/express/lib/router/index.js:312:12)
        at /Users/John/node_modules/express/lib/router/index.js:228:12
        at Function.match_layer (/Users/John/node_modules/express/lib/router/index.js:295:3)

node.js TypeError: path must be absolute or specify root to res.sendFile [failed to parse JSON]

Node version is `v0.11.13`

Memory usage during crash according to `sudo top` not raises over `3%`

Code that reproduces this error:

    var request = require(&#39;request&#39;)
    var nodedump = require(&#39;nodedump&#39;)

    request.get(&quot;http://pubapi.cryptsy.com/api.php?method=marketdatav2&quot;,function(err,res)
    {
        var data
        console.log( &quot;Data received.&quot; );
        data = JSON.parse(res.body)
        console.log( &quot;Data parsed.&quot;   );
        data = nodedump.dump(data)
        console.log( &quot;Data dumped.&quot;   ); 
        console.log( data )
    })


To check if that a recursion stack size problem I have ran next code with --stack-size=60000 parameter

    var depth = 0;

    (function recurse() {
        // log at every 500 calls
        (++depth % 500) || console.log(depth);
        recurse();
    })();

and have got

    264500 
    Segmentation fault

Then I ran code which gives me FATAL ERROR: CALL_AND_RETRY_LAST Allocation failed - process out of memory with the same --stack-size=60000 parameter and haven&#39;t got `Segmentation fault`. 

So I conclude `CALL_AND_RETRY_LAST` has nothing common with the recursion stack size.

How could I solve this problem? I believe there is enough free memory on my computer to finish this task successfully.

There are similar questions on stackoverflow but none of this questions are about `CALL_AND_RETRY_LAST` that&#39;s why I created separate question.

Content Type	Original Author	Original Content on Stackoverflow
Question	LouisK	View Question on Stackoverflow
Solution 1 - Linux	Yogu	View Answer on Stackoverflow
Solution 2 - Linux	rainabba	View Answer on Stackoverflow
Solution 3 - Linux	chadhamre	View Answer on Stackoverflow

Node.js - Get number of processors available

Linux Problem Overview

Linux Solutions

Solution 1 - Linux

Solution 2 - Linux

Solution 3 - Linux

Laravel Escaping All HTML in Blade Template

Call a function from another package in Go

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