In your terminal, type:

    scp your_username@remotehost.edu:foobar.txt /local/dir

replacing the username, host, remote filename, and local directory as appropriate.

If you want to access EC2 (or other service that requires authenticating with a private key), use the `-i` option:

    scp -i key_file.pem your_username@remotehost.edu:/remote/dir/foobar.txt /local/dir

From: http://www.hypexr.org/linux_scp_help.php

You can do this with the `scp` command. `scp` uses the SSH protocol to copy files across system by extending the syntax of `cp`.  

Copy something from another system to this system:  

    scp username@hostname:/path/to/remote/file /path/to/local/file

Copy something from this system to some other system:  

    scp /path/to/local/file username@hostname:/path/to/remote/file          

Copy something from some system to some other system:  

    scp username1@hostname1:/path/to/file username2@hostname2:/path/to/other/file   



scp is certainly the way to go, but for completeness you can also do:

    $ ssh host &#39;cat /path/on/remote&#39; &gt; /path/on/local

or

    $ cat /path/on/local | ssh host &#39;cat &gt; /path/on/remote&#39;

Note, this is UUOC, but `&lt; /path/on/local ssh host &#39;cat &gt; /path&#39;` could cause unnecessary confusion.

And to proxy between two hosts:

    $ ssh host1 &#39;cat /path/on/host1&#39; | ssh host2 &#39;cat &gt; /path/on/host2&#39;

If the SSH server support SFTP subsystem (this is part of SSH, and _unrelated_ to FTP), use sftp. If it don&#39;t, try scp.  

[CyberDuck][1] support all of them.


  [1]: http://cyberduck.ch/

I&#39;ve added .DS_Store to the .gitignore file, but it seems that it is only ignoring .DS_Store in the root directory, not in every folder and subfolder.

How do I fix this?

.gitignore all the .DS_Store files in every folder and subfolder

Joshua Bloch in &quot;*Effective Java*&quot; said that 

&gt; Use checked exceptions for
&gt; recoverable conditions and runtime
&gt; exceptions for programming errors
&gt; (Item 58 in 2nd edition)

Let&#39;s see if I understand this correctly.

Here is my understanding of a checked exception:

    try{
        String userInput = //read in user input
        Long id = Long.parseLong(userInput);
    }catch(NumberFormatException e){
        id = 0; //recover the situation by setting the id to 0
    }
**1. Is the above considered a checked exception?**

**2. Is RuntimeException an unchecked exception?**

Here is my understanding of an unchecked exception:

    try{
        File file = new File(&quot;my/file/path&quot;);
        FileInputStream fis = new FileInputStream(file);   
    }catch(FileNotFoundException e){
        
    //3. What should I do here?
        //Should I &quot;throw new FileNotFoundException(&quot;File not found&quot;);&quot;?
        //Should I log?
        //Or should I System.exit(0);?
    }

**4. Now, couldn&#39;t the above code also be a checked exception? I can try to recover the situation like this? Can I?** (Note: my 3rd question is inside the `catch` above)

    try{
        String filePath = //read in from user input file path
        File file = new File(filePath);
        FileInputStream fis = new FileInputStream(file);   
    }catch(FileNotFoundException e){
        //Kindly prompt the user an error message
        //Somehow ask the user to re-enter the file path.
    }
 
**5. Why do people do this?**

    public void someMethod throws Exception{

    }

Why do they let the exception bubble up? Isn&#39;t handling the error sooner better? Why bubble up? 

**6. Should I bubble up the exact exception or mask it using Exception?**

**Below are my readings**

https://stackoverflow.com/questions/499437/in-java-when-should-i-create-a-checked-exception-and-when-should-it-be-a-runtim

https://stackoverflow.com/questions/27578/when-to-choose-checked-and-unchecked-exceptions

Understanding checked vs unchecked exceptions in Java

I need to download a file from server to my desktop. (UBUNTU 10.04) I don&#39;t have a web access to the server, just ssh.

If it helps, my OS is Mac OS X and iTerm 2 as a terminal.

How to download a file from server using SSH?

<p>I need to download a file from server to my desktop. (UBUNTU 10.04) I don't have a web access to the server, just ssh.</p>
<p>If it helps, my OS is Mac OS X and iTerm 2 as a terminal.</p>


Does anybody know a way to perform a quick fuzzy search from linux console?

Quite often I come accross situation when I need to find a file in a project but I don&#39;t remember the exact filename. In [Sublime text editor][1] I would press Ctrl-P and type a part of the name, which will produce a list of the files to select from. That&#39;s an amazing feature I&#39;m quite happy with. The problem is that in most cases I have to browse a code in a console on remote machines via ssh. So I&#39;m wondering is there a tool similar to &quot;Go Anywhere&quot; feature for Linux console?


  [1]: http://www.sublimetext.com/2

Fuzzy file search in linux console

I wrote a shell script like this:

    #! /bin/sh
    ...
    ls | grep &quot;android&quot;
    ...

and the output is :

    android1 
    android2
    xx_android
    ...

I want to add a number in each file, like this:

        1 android1 
        2 android2
        3 XX_android
        ...
        please choose your dir number:

and then wait for the user input line number x, the script reads the line number back then process the corresponding dir. How can we do this in shell ? Thanks !





How to add line number for output, prompt for line, then act based on input?

I have this proxy address: `125.119.175.48:8909`

How can I perform a HTTP request using cURL like `curl http://www.example.com`, but specifying the proxy address of my network? 
      

performing HTTP requests with cURL (using PROXY)

Which header file should I invoke with `#include` to be able to use PATH_MAX as an int for sizing a string?

I want to be able to declare:

    char *current_path[PATH_MAX];

But when I do so my compiler (Clang/LLVM on Linux) issues the following error:


    recursive_find6.c:29:20: error: use of undeclared identifier &#39;PATH_MAX&#39;
    char *current_path[PATH_MAX];
                       ^

I tried doing a google search but still no luck.

`#include &lt;limits.h&gt;` Does NOT fix the problem/error.

Am I also correct that the value of PATH_MAX is an int?

Where is PATH_MAX defined in Linux?

I know you can do `mkdir` to create a directory and `touch` to create a file, but is there no way to do both operations in one go?

i.e. if I want to do the below when the folder `other` does not exist:

    cp /my/long/path/here/thing.txt /my/other/path/here/cpedthing.txt

Error:

    cp: cannot create regular file `/my/other/path/here/cpedthing.txt&#39;: No such file or directory

Has anyone come up with a function as a workaround for this?

Unix - create path of folders and file

I want my `.bash_history` file to be unlimited. e.g. So I can always go back and see how I built/configured something, or what that nifty command was, or how some command broke something weeks ago. How do I change this setting?

Unlimited Bash History

I have a CSV-like file, and I would like to sort it by column priority, like [&quot;ORDER BY&quot; in SQL](https://dev.mysql.com/doc/refman/8.0/en/sorting-rows.html). For example, given the following rows,

    3;1;2
    1;3;2
    1;2;3
    2;3;1
    2;1;3
    3;2;1

If &quot;ORDER BY&quot; were `column2, column1, column3`, the result would be:

    2;1;3
    3;1;2
    1;2;3
    3;2;1
    1;3;2
    2;3;1

I&#39;d like to know how to get this same result using the `sort` command on Unix.

Sort CSV file by multiple columns using the &quot;sort&quot; command

    foo=&quot;/sdf/here/jfds&quot;
    bar=&quot;${foo##*/}&quot;

Can anyone explain how the &quot;`${foo##*/}`&quot; expression works? I understand it will return the string after the last forward slash (i.e. jfds). However, I have no idea how it does or what this type of expression is called?

Expression after last specific character

I have some code written in Go which I am trying to update to work with the latest weekly builds. (It was last built under r60). Everything is now working except for the following bit:

     if t, _, err := os.Time(); err == nil {
       port[5] = int32(t)
     }

Any advice on how to update this to work with the current Go implementation?

Obtaining a Unix Timestamp in Go Language (current time in seconds since epoch)

I opened a ssh tunnel as described in this post: https://stackoverflow.com/questions/2807118/zend-db-how-to-connect-to-a-mysql-database-over-ssh-tunnel

But now I don&#39;t know what I actually did. Does this command affect anything on the server?
And how do I close this tunnel, because now I can&#39;t use my local mysql properly.

I use OSX Lion and the server runs on Ubuntu 11.10.

How to close this ssh tunnel?

I want to extract the public and private key from my `PKCS#12` file for later use in SSH-Public-Key-Authentication. 

Right now, I&#39;m generating keys via ssh-keygen which I put into `.ssh/authorized_key`, respective somewhere on the client-side.

In future, I want to use the keys from a `PKCS#12` container, so I&#39;ve to extract the public-key first from `PKCS#12` and then put them into the `.ssh/authorized_keys` file. Is there any chance to get this working via `openssl`? Are the keys in `PKCS#12` compatible for ssh-public-key authentication?

Extract public/private key from PKCS12 file for later use in SSH-PK-Authentication

I have changed several files in a git repository, but have not committed them yet.

I can get a list of the changes by just invoking `git status`. But how do I get a listing of the *lines* or the *content* that I have changed, in addition to the filenames?

I initially thought about using [git diff][1], but it seems to be useful only for comparing already commited changes.

Usually I just do `meld .`, but on this case I&#39;m connected to an external server via ssh.


  [1]: http://schacon.github.com/git/git-diff.html

git - diff of current changes before committing

I need to do the SSH key audit for GitHub, but I am not sure how do find my RSA key fingerprint. I originally followed a guide to generate an SSH key on Linux.

What is the command I need to enter to find my current RSA key fingerprint?

Calculate RSA key fingerprint

Here&#39;s what&#39;s happening to me: I start tmux sessions using `tmux -L name1`, `tmux -L name2`; then I detatch them using &lt;kbd&gt;ctrl&lt;/kbd&gt;+&lt;kbd&gt;B&lt;/kbd&gt;+&lt;kbd&gt;d&lt;/kbd&gt;. Then I try to get a list of the currently running sessions on my computer. However, when I run `tmux ls`, I get an error message: 

    failed to connect to server: Connection refused

Is this a bug? I&#39;m familiar with screen; I regard `screen -ls` as a very useful function since I might start a session and leave it running for weeks before the next time I attach to it. Because of this, the ability to list current running tmux sessions is quite important for me. Why does `tmux ls` return a &quot;connection refused&quot; error when I know tmux is running?

Content Type	Original Author	Original Content on Stackoverflow
Question	NiLL	View Question on Stackoverflow
Solution 1 - Linux	Josh1billion	View Answer on Stackoverflow
Solution 2 - Linux	raj_gt1	View Answer on Stackoverflow
Solution 3 - Linux	William Pursell	View Answer on Stackoverflow
Solution 4 - Linux	J-16 SDiZ	View Answer on Stackoverflow

How to download a file from server using SSH?

Linux Problem Overview

Linux Solutions

Solution 1 - Linux

Solution 2 - Linux

Solution 3 - Linux

Solution 4 - Linux

Understanding checked vs unchecked exceptions in Java

.gitignore all the .DS_Store files in every folder and subfolder

Attributions