Deb is not a command. You need to edit your `/etc/apt/sources.list` file and add the following line

    deb http://downloads-distro.mongodb.org/repo/ubuntu-upstart dist 10gen

to the end of the file.

Then, update your system and then install MongoDB. Assuming mongodb is the package you need then run these commands:

    sudo apt-get update
    sudo apt-get install mongodb



How do I create an empty mutable two dimensional array in Rust?

This is what I have tried so far:

    let mut state[[u8 * 4] * 4];

This produces the error

&lt;!-- language: none --&gt;

    error: expected one of `:`, `;`, `=`, or `@`, found `[`
     --&gt; src/main.rs:2:18
      |
    2 |     let mut state[[u8 * 4] * 4];
      |                  ^ expected one of `:`, `;`, `=`, or `@` here



Creating two dimensional arrays in Rust

I saw this recently, thought it was interesting.  But I don&#39;t really understand what it does?

Ex.  I have a rails app and I want to bootstrap some json, so that I don&#39;t have to make a second request.  Normally I would write something like this.

`&lt;%= raw @model.to_json %&gt;`
or
`&lt;%= @model.to_json.html_safe %&gt;`

I have to send the message `raw` or `html_safe` or the json will be html escaped and thus not parsed correctly.  However, this seems to work too.

`&lt;%== @model.to_json %&gt;`

But I can&#39;t find any documentation.

Does anyone know what this does exactly?  i.e.  Is it the exact same as calling `html_safe` or `raw`?  Or is there more to it?

What does &lt;%== %&gt; do in rails erb?

When I tried to install mongoDb in my AWS EC2 Linux instance:Ubuntu 12.04.1 LTS,

    deb http://downloads-distro.mongodb.org/repo/ubuntu-upstart dist 10gen

I get this following error, meaning deb command is not found.
```
$ deb Sorry, command-not-found has crashed! Please file a bug report
at: https://bugs.launchpad.net/command-not-found/+filebug Please
include the following information with the report:
 
command-not-found version: 0.2.44
```
Can someone please help me find out how to install deb in my AWS instance?

AWS EC2 Ubuntu 12.04.1 LTS: deb command-not-found

When I tried to install mongoDb in my AWS EC2 Linux instance:Ubuntu 12.04.1 LTS,
<pre><code class="hljs language-arduino">deb http://downloads-distro.mongodb.org/repo/ubuntu-upstart dist 10gen
</code></pre>
I get this following error, meaning deb command is not found.
<pre><code class="hljs language-ruby">$ deb Sorry, command-not-found has crashed! Please file a bug report
at: https://bugs.launchpad.net/command-not-found/+filebug Please
include the following information with the report:
 
command-not-found version: 0.2.44
</code></pre>
Can someone please help me find out how to install deb in my AWS instance?

It would just be cool if your shell script helps you to **safely remove your flash disk** after finishing its job. The solution is expected to meet the following needs:

 1. Suppose the flash disk is mounted as `/media/A` together with many other flash disks and the code can selectively just remove `/media/A` without interfering other disks. For example, I can pass `/media/A` as an argument.
 2. A light solution. Installing another package of size 100MB to finish the task drives one crazy.
 3. I know some commands like `hdparm` except their documents are hard to read. If one can offer me a solution I hope he/she can offer also the explanation of the parameters, etc.
 4. Best if the code can handle all kinds of flash disks (for example, my old one bought in 2003 with 32&amp;nbsp;MB) (and portable disks optionally).
 5. It should achieve the exact effect as right clicking the disk &amp;rarr; clicking &quot;safely Remove Drive&quot;. The safety concern will prevail, otherwise one may just unplug the disk which usually won&#39;t hurt.



Linux (Ubuntu): safely remove a USB flash disk via the command line

Here is how the error output is if I run `virtualbox` from the terminal. How to correct it? I am on a Ubuntu 12.10 64bit machine.

    virtualbox
    WARNING: The character device /dev/vboxdrv does not exist.
    	 Please install the virtualbox-ose-dkms package and the appropriate
    	 headers, most likely linux-headers-generic.
    
    	 You will not be able to start VMs until this problem is fixed.

EDIT:

I have both the latest `linux-headers-generic` and `virtualbox-ose-dkms` packages

How to correct virtualbox installation

In the windows environment you will have .m2 folder in C:\Users\user_name location and you will copy your settings.xml file to it in order to setup your proxy settings and nexus repository locations and etc.

So What I have to done on Ubuntu environment to get similar setup after installing maven on it. 

.m2 , settings.xml in Ubuntu

Is it possible in Linux command line to have a command repeat every *n* seconds?

Say, I have an import running, and I am doing

    ls -l

to check if the file size is increasing. I would like to have a command to have this repeat automatically.

Repeat command automatically in Linux

I used the following command to convert and merge all the `jpg` files in a directory to a single pdf file.

    convert *.jpg file.pdf

The files in the directory are numbered from `1.jpg` to `123.jpg`. The convertion went fine but after converting the pages were all mixed up. I wanted the pdf to have pages from `1.jpg` to `123.jpg` in the same order as they are named. I tried with the following command as well:

    cd 1 
    FILES=$( find . -type f -name &quot;*jpg&quot; | cut -d/ -f 2)
    mkdir temp &amp;&amp; cd temp 
    for file in $FILES; do 
        BASE=$(echo $file | sed &#39;s/.jpg//g&#39;);
        convert ../$BASE.jpg $BASE.pdf; 
        done &amp;&amp; 
    pdftk *pdf cat output ../1.pdf &amp;&amp; 
    cd .. 
    rm -rf temp

But still no luck. Operating platform Linux.

Merge multiple jpg into single pdf in Linux

When would I use SNS versus SQS, and why are they always coupled together?


What is the difference between Amazon SNS and Amazon SQS?

**Update:** For future reference, Amazon have now updated the documentation from what was there at time of asking. As per @Loren Segal&#39;s comment below:-

&gt; We&#39;ve corrected the docs in the latest preview release to document this parameter properly. Sorry about the mixup! 

---

I&#39;m trying out the developer preview of [the AWS SDK for Node.Js](http://aws.amazon.com/about-aws/whats-new/2012/12/04/introducing-the-aws-sdk-for-node-js/) and want to upload a zipped tarball to S3 using `putObject`.

According to [the documentation](http://docs.amazonwebservices.com/AWSJavaScriptSDK/latest/AWS/S3/Client.html#putObject-property), the `Body` parameter should be...

&gt; Body - (Base64 Encoded Data)

...therefore, I&#39;m trying out the following code...

    var AWS = require(&#39;aws-sdk&#39;),
        fs = require(&#39;fs&#39;);
    
    // For dev purposes only
    AWS.config.update({ accessKeyId: &#39;key&#39;, secretAccessKey: &#39;secret&#39; });
    
    // Read in the file, convert it to base64, store to S3
    fs.readFile(&#39;myarchive.tgz&#39;, function (err, data) {
      if (err) { throw err; }
    
      var base64data = new Buffer(data, &#39;binary&#39;).toString(&#39;base64&#39;);
    
      var s3 = new AWS.S3();
      s3.client.putObject({
        Bucket: &#39;mybucketname&#39;,
        Key: &#39;myarchive.tgz&#39;,
        Body: base64data
      }).done(function (resp) {
        console.log(&#39;Successfully uploaded package.&#39;);
      });
      
    });

Whilst I can then see the file in S3, if I download it and attempt to decompress it I get an error that the file is corrupted. Therefore it seems that my method for &#39;base64 encoded data&#39; is off.

Can someone please help me to upload a binary file using `putObject`?

Upload a binary file to S3 using AWS SDK for Node.js

I&#39;m getting this error intermittently.

I have a program that uses the java aws sdk and loads over the 10s of thousands of small files to s3. I see this error intermittently.

Could not find any helpful answer after doing a quick search on the internet.

Note the calling program is single threaded. The underlying aws java sdk does seem to use worker threads.



    Status Code: 409, AWS Service: Amazon S3, AWS Request ID: 75E16E8DE2193CA6, AWS Error Code: OperationAborted, AWS Error Message: A conflicting conditional operation is currently in progress against this resource. Please try again., S3 Extended Request ID: 0uquw2YEoFamLldm+c/p412Lzd8jHJGFBDz3h7wN+/4I0f6hnGLkPMe+5LZazKnZ
        at com.amazonaws.http.AmazonHttpClient.handleErrorResponse(AmazonHttpClient.java:552)
        at com.amazonaws.http.AmazonHttpClient.executeHelper(AmazonHttpClient.java:289)
        at com.amazonaws.http.AmazonHttpClient.execute(AmazonHttpClient.java:170)
        at com.amazonaws.services.s3.AmazonS3Client.invoke(AmazonS3Client.java:2648)
        at com.amazonaws.services.s3.AmazonS3Client.createBucket(AmazonS3Client.java:578)
        at com.amazonaws.services.s3.AmazonS3Client.createBucket(AmazonS3Client.java:503)
 

AWS Error Message: A conflicting conditional operation is currently in progress against this resource

I&#39;ve been using MySQL for a fair while now and I&#39;m comfortable with its structure &amp; SQL Queries etc.

Currently building a new system in AWS and I&#39;ve been looking at DynamoDB. Currently I only know a little about it.

Is one better then the other? 

What are the advantage of DynamoDB?

what is the transition like from MySQL queries etc to this flat style DB?


AWS MySQL RDS vs AWS DynamoDB

I installed Ubuntu 12.04 on my instance and am trying to install packages using apt-get, but I am getting the following error:

    sudo: apt-get: command not found

How do I fix this?

How to fix apt-get: command not found on AWS EC2?

I have installed sbt on Ubuntu.

    :~/bin/sbt/bin$ ls
    classes    sbt      sbt-launch.jar       target
    jansi.jar  sbt.bat  sbt-launch-lib.bash  win-sbt

However, whenever I try to launch sbt (from the same directory where sbt is located) it does not work:

    No command &#39;sbt&#39; found, did you mean:
     Command &#39;skt&#39; from package &#39;latex-sanskrit&#39; (universe)
     Command &#39;sb2&#39; from package &#39;scratchbox2&#39; (universe)
     Command &#39;sbd&#39; from package &#39;cluster-glue&#39; (main)
     Command &#39;mbt&#39; from package &#39;mbt&#39; (universe)
     Command &#39;sbmt&#39; from package &#39;atfs&#39; (universe)
     Command &#39;lbt&#39; from package &#39;lbt&#39; (universe)
     Command &#39;st&#39; from package &#39;suckless-tools&#39; (universe)
     Command &#39;sb&#39; from package &#39;lrzsz&#39; (universe)

I am new to linux and I have no idea how to tackle this issue.


Content Type	Original Author	Original Content on Stackoverflow
Question	Futur	View Question on Stackoverflow
Solution 1 - Ubuntu	jokerdino	View Answer on Stackoverflow

AWS EC2 Ubuntu 12.04.1 LTS: deb command-not-found

Ubuntu Problem Overview

Ubuntu Solutions

Solution 1 - Ubuntu

What does <%== %> do in rails erb?

Creating two dimensional arrays in Rust

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