Use this

    $ dig +short stackoverflow.com

    69.59.196.211

or this

    $ host stackoverflow.com

    stackoverflow.com has address 69.59.196.211
    stackoverflow.com mail is handled by 30 alt2.aspmx.l.google.com.
    stackoverflow.com mail is handled by 40 aspmx2.googlemail.com.
    stackoverflow.com mail is handled by 50 aspmx3.googlemail.com.
    stackoverflow.com mail is handled by 10 aspmx.l.google.com.
    stackoverflow.com mail is handled by 20 alt1.aspmx.l.google.com.


You can use:

    nslookup www.example.com

    insert into table select * from table where primarykey=1

I just want to copy one row to insert into the same table (i.e., I want to duplicate an existing row in the table) but I want to do this without having to list all the columns after the &quot;select&quot;, because this table has too many columns.

But when I do this, I get the error:
 &gt; Duplicate entry &#39;xxx&#39; for key 1

I can handle this by creating another table with the same columns as a temporary container for the record I want to copy:

    create table oldtable_temp like oldtable;
    insert into oldtable_temp select * from oldtable where key=1;
    update oldtable_tem set key=2;
    insert into oldtable select * from oldtable where key=2;

Is there a simpler way to solve this?

In MySQL, can I copy one row to insert into the same table?

I want to prompt a user for a number of random numbers to be generated and saved to a file. He gave us that part. The part we have to do is to open that file, convert the numbers into a list, then find the mean, standard deviation, etc. without using the easy built-in Python tools.

I&#39;ve tried using `open` but it gives me invalid syntax (the file name I chose was &quot;numbers&quot; and it saved into `&quot;My Documents&quot;` automatically, so I tried `open(numbers, &#39;r&#39;)` and `open(C:\name\MyDocuments\numbers, &#39;r&#39;)` and neither one worked).

How do you read a file into a list in Python?

Is there any Linux command to translate a domain name to an IP address?

Linux command to translate domain name to IP

<p>Is there any Linux command to translate a domain name to an IP address?</p>


I&#39;m using grep to match string in a file. Here is an example file:

    example one,
    example two null,
    example three,
    example four null,

`grep -i null myfile.txt` returns 

    example two null,
    example four null,

How can I return matched lines together with their line numbers like this:

      example two null, - Line number : 2
      example four null, - Line number : 4
      Total null count : 2

I know -c returns total matched lines, but I don&#39;t how to format it properly to add `total null count` in front, and I don&#39;t know how to add the line numbers.

What can I do?

How can I format my grep output to show line numbers at the end of the line, and also the hit count?

How do &quot;modern&quot; `cron` daemons *internally* schedule their jobs?  Some `crond`s used to schedule a run every so often via `at`.  So after a crontab is written out, does `crond`:

 1. Parse the crontab for all future events and the sleep for the intervals?
 2. Poll an aggregated crontab database every minute to determine if the current time matches the schedule pattern?
 3.  Other?

Thanks,



How does cron internally schedule jobs?

What does `/bin/sh -c` mean? What does `-c` do?

What is /bin/sh -c?

Is there a function that returns how much space is free on a drive partition given a directory path?

How do I programmatically get the free disk space for a directory in Linux

I want to know how to create a simple desktop environment, such as KDE, Gnome and LXDE, for Linux, or specifically, Ubuntu/Kubuntu, but I do not know how to begin and how complex it is.

I want to create a simple, efficient and lightweight desktop and to reproduce some good features from KDE, Gnome and Windows XP. I do not want to reinvent the wheel, I want to design the graphical interface and main dialogs.

I could use C++ with Qt, or maybe with X11 calls. A simple desktop like TWM would be the first step, then I could add taskbar, start menu, new features and play with new ideas.

Thanks.


**Edit**

I have installed icewm and I think it is what I need to begin. On the login screen, I can choose if I use KDE (desktop environment) or icewm (window manager). I do not understand what a window manager actually is.

I have downloaded icewm source code and I am confused. There are some concepts that I have to understand, such as, what happens after the login screen when the desktop is loaded, how a window works, etc.


**Edit 2**

I think I need a good tutorial. I have to understand how a Window Manager or Desktop Environment work. There are some concepts that I have to know.


How to create a simple desktop environment?

1. what is the maximum value of data type INTEGER in sqlite3 ? 
2. How do you store ip address in database ? 
3. What is attached ?
4. How to create table which belongs to a specific database using sql ddl?
5. What is this error about ? 

&gt; error while the list of system
&gt; catalogue : no such table: temp.sqlite_master 
&gt; Unable to execute statement


6. Does sqlite3 text data type supoports unicode?
Thanks. 


SQLite3 Integer Max Value

Bellow method is validating if string is correct IPv4 address it returns true if it is valid. Any improvements in regex and elegance would be very appreciated: 

    public static boolean validIP(String ip) {
        if (ip == null || ip.isEmpty()) return false;
        ip = ip.trim();
        if ((ip.length() &lt; 6) &amp; (ip.length() &gt; 15)) return false;

        try {
            Pattern pattern = Pattern.compile(&quot;^(?:(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\\.){3}(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)$&quot;);
            Matcher matcher = pattern.matcher(ip);
            return matcher.matches();
        } catch (PatternSyntaxException ex) {
            return false;
        }
    }

Validating IPv4 string in Java

I was playing with sockets on local machine with no network connection. See below:

    IPAddress address = IPAddress.Any; // doesn&#39;t work
    IPAddress address = IPAddress.Parse(&quot;::1&quot;); // works

So what is exactly `::1` IP address ? Is it the default available IP address or it&#39;s the loopback address ? what happens to above code (working line) on a machine with dedicated IP address and network connection ?

EDIT:

exact code is used to bind a specific IP address to socket. Here it is:

    ServicePoint sp = ServicePointManager.FindServicePoint(uri);
    sp.BindIPEndPointDelegate = new BindIPEndPoint(Bind);
    // here&#39;s the bind delegate:
    private IPEndPoint Bind(ServicePoint sp, IPEndPoint ep, int retryCount)
    {
       return new IPEndPoint(IPAddress.Parse(&quot;::1&quot;), 0);
    }

What is IP address &#39;::1&#39;?

&gt; **Possible Duplicate:**  
&gt; [Is there an easy way to convert String to Inetaddress in Java?](https://stackoverflow.com/questions/2309049/is-there-an-easy-way-to-convert-string-to-inetaddress-in-java)  

&lt;!-- End of automatically inserted text --&gt;

I&#39;m  trying to convert a string(representing an IP address, e.g. `10.0.2.50`) into an `InetAddress` obj. 

According to the API it is possible to create an Object providing a String representing a hostname (e.g. `www.google.ch`). This is not an option for me since I do not have the hostname for each InetAddress object I want to create(besides that it takes too long).

Is it possible to convert a String (e.g. `10.0.2.50`) into an `InetAddress` obj.? (according to the api it is possible to do so if you have the IP as `byte[]`, but how do I convert a `String` containing an IP into `byte[]`?)

Java: Convert a String (representing an IP) to InetAddress

I am trying to convert an address specified by an IP number or a name, both in String (i.e. `localhost` or `127.0.0.1`), into an *InetAdress* object. There&#39;s no constructor but rather static methods that return an *InetAddress*. So if I get a host name it&#39;s not a problem, but what if I get the IP number? There&#39;s one method that gets *byte[]* but I&#39;m not sure how that can help me. All other methods gets the host name.

[InetAddress API documentation][1]


  [1]: http://download.oracle.com/javase/1.4.2/docs/api/java/net/InetAddress.html

Creating InetAddress object in Java

I want to get the domain name for where the script is running. How can that be done with PHP?
I see that `$_SERVER[&#39;HTTP_HOST&#39;]` as well as `$_SERVER[&#39;SERVER_NAME&#39;]` contain this information.
Will that variable always work and should I use one over the other?

Thank you.

PHP get domain name

I need to validate a domain name:

**google.com**

**stackoverflow.com**

So a domain in its rawest form - not even a subdomain like www.

 1. Characters should only be **a-z** | **A-Z** | **0-9** and **period**(.) and **dash**(-)
 2. The domain name part should not start or end with dash (-) *(e.g. -google-.com)*
 3. The domain name part should be between 1 and 63 characters long
 4. &lt;strike&gt;The extension (TLD) can be anything under #1 rules for now, I may validate them against a list later, it should be 1 or more characters though&lt;/strike&gt;

&lt;strike&gt;Edit: TLD is apparently 2-6 chars as it stands&lt;/strike&gt;

**no. 4 revised:** TLD should actually be labelled &quot;subdomain&quot; as it should include things like .co.uk -- I would imagine the only validation possible (apart from checking against a list) would be &#39;after the first dot there should be one or more characters under rules #1

Thanks very much, believe me I did try!

What is a regular expression which will match a valid domain name without a subdomain?

I plan on buying two domain names for the same site.  Depending on which domain is used I plan on providing slightly different data on the page.  Is there a way for me to detect the actual domain name that the page is loading from so that I know what to change my content to?

I&#39;ve looked around for stuff like this but most of it doesn&#39;t work the way I want it to.

For instance when using

    document.write(document.location)

on [JSFiddle][1] it returns

&gt; `http://fiddle.jshell.net/_display/`

i.e. the actual path or whatever that is.


  [1]: http://jsfiddle.net/LSAP5/

Get The Current Domain Name With Javascript (Not the path, etc.)

I have 3 domain names and am trying to host all 3 sites on one server (a Digital Ocean droplet) using Nginx.

mysite1.name
mysite2.name
mysite3.name

Only 1 of them works.  The other two result in 403 errors (in the same way).

In my nginx error log, I see: `[error] 13108#0: *1 directory index of &quot;/usr/share/nginx/mysite2.name/live/&quot; is forbidden`.

My sites-enabled config is:

    server {
            server_name www.mysite2.name;
            return 301 $scheme://mysite2.name$request_uri;
    }
    server {
            server_name     mysite2.name;
    
            root /usr/share/nginx/mysite2.name/live/;
            index index.html index.htm index.php;
    
            location / {
                    try_files $uri $uri/ /index.html index.php;
            }
    
            location ~ \.php$ {
                    fastcgi_split_path_info ^(.+\.php)(/.+)$;
                    fastcgi_pass unix:/var/run/php5-fpm.sock;
                    fastcgi_index index.php;
                    include fastcgi_params;
            }
    }

All 3 sites have nearly identical config files.

Each site&#39;s files are in folders like /usr/share/nginx/mysite1.name/someFolder, and then /usr/share/nginx/mysite1.name/live is a symlink to that. (Same for mysite2 and mysite3.)

I&#39;ve looked at https://stackoverflow.com/questions/6795350/nginx-403-forbidden-for-all-files?rq=1 but that didn&#39;t help. 

Any ideas on what might be wrong?

Content Type	Original Author	Original Content on Stackoverflow
Question	Frank	View Question on Stackoverflow
Solution 1 - Linux	unutbu	View Answer on Stackoverflow
Solution 2 - Linux	Dirk Vollmar	View Answer on Stackoverflow

Linux command to translate domain name to IP

Linux Problem Overview

Linux Solutions

Solution 1 - Linux

Solution 2 - Linux

How do you read a file into a list in Python?

In MySQL, can I copy one row to insert into the same table?

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