That&#39;s not an error - it&#39;s normal behavior. It just informs you that once started the in/output is removed from your console.

To avoid the message you need to start it like

    nohup php server1.php &lt;/dev/null &amp;&gt;/dev/null &amp;


If you want to see the output of the executed command,You need to follow this step,
execute the command $tailf nohup.out 

Please note : Nohup command creates a file with name nohup.out in same location where you have executed the nohup command .


Is it possible to show the `adb logcat` for a `tcpip` device in Android Studio? I am writing a application that utilizes the USB port and I cannot use it for `adb usb`.

Currently, I am using the following instruction to view the logcat in Command Prompt, but it would be nice if this was integrated into AS:
http://developer.android.com/tools/help/adb.html#wireless

Use adb over tcpip in Android Studio?

I have two `java.util.Optional` instances and I want to get an `Optional` that either:

- Has the value of the first Optional, if it has a value.
- Has the value of the second Optional, if it has a value.
- Is empty of neither Optional has a value.

Is there a straight-forward way to do that, i.e. is there already some API to do that?

The following expressions will do that, but I have to mention the first optional twice:

    firstOptional.isPresent() ? firstOptional : secondOptional

This is exactly what `com.google.common.base.Optional.or()` does, but that method is not present in Java 8&#39;s API.

---

The accepted answer by _aioobe_ lists a few alternative approaches to overcome this omission of the `Optional` API right where such a value has to be computed (which answers my question). I&#39;ve now opted to add a utility function to my codebase:

	public static &lt;T&gt; Optional&lt;T&gt; or(Optional&lt;T&gt; a, Optional&lt;T&gt; b) {
		if (a.isPresent())
			return a;
		else
			return b;
	}


Get value from one Optional or another

I want to start my server through nohup.php but the command is not running and displays following error 
&gt;nohup:ignoring input and appending output to &#39;nohup.out&#39;

I am using ssh through putty, this is what i am doing

&gt;nohup php server1.php

nohup:ignoring input and appending output to &#39;nohup.out&#39;

I want to start my server through nohup.php but the command is not running and displays following error
>nohup:ignoring input and appending output to 'nohup.out'
I am using ssh through putty, this is what i am doing
>nohup php server1.php

 Thank you in advance for you time in helping with this issue.. 

&gt; preg_match(): Compilation failed: invalid range in character class at offset 20 session.php on line 278

This stopped working all of a sudden after months of working, after a PHP upgrade on our server.

Here is the code

        else{
         /* Spruce up username, check length */
         $subuser = stripslashes($subuser);
         if(strlen($subuser) &lt; $config[&#39;min_user_chars&#39;]){
            $form-&gt;setError($field, &quot;* Username below &quot;.$config[&#39;min_user_chars&#39;].&quot;characters&quot;);
         }
         else if(strlen($subuser) &gt; $config[&#39;max_user_chars&#39;]){
            $form-&gt;setError($field, &quot;* Username above &quot;.$config[&#39;max_user_chars&#39;].&quot;characters&quot;);
         }


         /* Check if username is not alphanumeric */
        /* PREG_MATCH CODE */

         else if(!preg_match(&quot;/^[a-z0-9]([0-9a-z_-\s])+$/i&quot;, $subuser)){      	
            $form-&gt;setError($field, &quot;* Username not alphanumeric&quot;);
         }


        /* PREG_MATCH CODE */


         /* Check if username is reserved */
         else if(strcasecmp($subuser, GUEST_NAME) == 0){
            $form-&gt;setError($field, &quot;* Username reserved word&quot;);
         }
         /* Check if username is already in use */
         else if($database-&gt;usernameTaken($subuser)){
            $form-&gt;setError($field, &quot;* Username already in use&quot;);
         }
         /* Check if username is banned */
         else if($database-&gt;usernameBanned($subuser)){
            $form-&gt;setError($field, &quot;* Username banned&quot;);
         }
      }




preg_match(): Compilation failed: invalid range in character class at offset

I&#39;m trying to go through all of the files in a directory, and if there is a directory, go through all of its files and so on until there are no more directories to go to. Each and every processed item will be added to a results array in the function below. It is not working though I&#39;m not sure what I can do/what I did wrong, but the browser runs insanely slow when this code below is processed, any help is appreciated, thanks!

## Code:

        function getDirContents($dir){
            $results = array();
            $files = scandir($dir);

                foreach($files as $key =&gt; $value){
                    if(!is_dir($dir. DIRECTORY_SEPARATOR .$value)){
                        $results[] = $value;
                    } else if(is_dir($dir. DIRECTORY_SEPARATOR .$value)) {
                        $results[] = $value;
                        getDirContents($dir. DIRECTORY_SEPARATOR .$value);
                    }
                }
        }

        print_r(getDirContents(&#39;/xampp/htdocs/WORK&#39;));

List all the files and folders in a Directory with PHP recursive function

I have four conditions that I need to go through and I thought it would be best to use the `switch` statement in PHP. However, I need to check whether an integer is, let&#39;s say, less than or equal, or greater than and equal.

    switch ($count) {
        case 20:
            $priority = &#39;low&#39;;
            break;

        case 40:
            $priority = &#39;medium&#39;;
            break;

        case 60:
            $priority = &#39;high&#39;;
            break;

        case 80:
            $priority = &#39;severe&#39;;
            break;
    }

With an `if()` statement it would look like the following:

    if ($count &lt;= 20) {
        $priority = &#39;low&#39;;
    } elseif ($count &lt;= 40) {
        $priority = &#39;medium&#39;;
    } elseif ($count &lt;= 60) {
        $priority = &#39;high&#39;;
    } else {
        $priority = &#39;severe&#39;;
    }

Is that possible in `switch-case`?


Using comparison operators in a PHP &#39;switch&#39; statement

I have table of dogs in my DB and I want to retrieve **`N latest added dogs`**. 

Only way that I found is something like this:

    Dogs:all()-&gt;where(time, &lt;=, another_time);

Is there another way how to do it? For example something like this `Dogs:latest(5);`

Thank you very much for any help :)

Laravel: How to get last N entries from DB

I dont want to allow users to access my site with Microsoft Internetexplorer (ANY VERSION).

What I&#180;ve found so far was to detect if it&#180;s lower or equal version 10.

A very annoing thing: Internetexplorer &gt;v10 doesn&#180;t admit to be a InternetExplorer.

What i&#180;ve found and tried so far:

    if(navigator.appVersion.indexOf(&quot;MSIE&quot;)!=-1){
    alert(&quot;You use IE. That&#180;s no good.&quot;);
    }

or

    if ( $.browser.msie ) {
    alert( $.browser.version );
    }

and

[http://msdn.microsoft.com/en-us/library/ie/ms537509%28v=vs.85%29.aspx][1]

I would use any solution if it is in javascript, jquery or php if there is one.



  [1]: http://msdn.microsoft.com/en-us/library/ie/ms537509%28v=vs.85%29.aspx

Detect if any kind of IE (MSIE)

Ideally, I would be able to use a program like 

    find [file or directory name]

to report the paths with matching filenames/directories. Unfortunately this seems to only check the current directory, not the entire folder.

I&#39;ve also tried locate and which, but none find the file, even though I know its on the computer somewhere.

How can I find a file/directory that could be anywhere on linux command line?

I recently installed the Anaconda version of Python. Now when I type `python` into the terminal it opens the Anaconda distribution rather than the default distribution. How do I get it to use the default version for the command `python` on Linux ([Ubuntu&amp;nbsp;12.04][1] (Precise&amp;nbsp;Pangolin))?

  [1]: https://en.wikipedia.org/wiki/Ubuntu_version_history#Ubuntu_12.04_LTS_.28Precise_Pangolin.29


Use the default Python rather than the Anaconda installation when called from the terminal

I am getting the error &quot;No space left on device&quot; when i tried to scp some files to a centos machine, 

tried to check:

    [root@...]# df -h
    Filesystem            Size  Used Avail Use% Mounted on
    /dev/mapper/VolGroup00-LogVol01 18G   18G     0 100% /

And when I do

`du -sh /` -&gt; it gives only 5G

    [... ~]$ df -i /
    Filesystem            Inodes   IUsed   IFree IUse% Mounted on
    /dev/mapper/VolGroup00-LogVol01
                         4685824  209516 4476308    5% /


seems like file system is full.
How can i find which one is taking these much size?

No space left on device

    KDIR ?= $(shell uname -r)

What is the meaning of `?=`?

I have understood the difference between `:=`, `+=` and `=` from another thread available in Stack Overflow, but unable to find the explanation for `?=`.

What is ?= in Makefile

I have a Linode server running Ubuntu 12.04 LTS and MongoDB instance (service is running and CAN connect locally) that I can&#39;t connect to from an outside source.


I have added these two rules to my IP tables, where &lt; ip address &gt; is the server I want to connect FROM (as outlined in this [MongoDB reference](http://docs.mongodb.org/manual/tutorial/configure-linux-iptables-firewall/)):

&lt;code&gt;iptables -A INPUT -s &lt; ip-address &gt; -p tcp --destination-port 27017 -m state --state NEW,ESTABLISHED -j ACCEPT
&lt;/code&gt;

&lt;code&gt;iptables -A OUTPUT -d &lt; ip-address &gt; -p tcp --source-port 27017 -m state --state ESTABLISHED -j ACCEPT
&lt;/code&gt;

And I see the rule in my IP table allowing connections on 27017 to and from &lt; ip address &gt; however when I try to connect from , &lt; ip address &gt; to my mongo database using a command like this:

&lt;code&gt;mongo databasedomain/databasename -u username -p password&lt;/code&gt;

I get this error:

&lt;code&gt;2014-07-22T23:54:03.093+0000 warning: Failed to connect to databaseserverip:27017, reason: errno:111 Connection refused
2014-07-22T23:54:03.094+0000 Error: couldn&#39;t connect to server &lt; ip address &gt;:27017 (databaseserverip), connection attempt failed at src/mongo/shell/mongo.js:148
exception: connect failed&lt;/code&gt;

Any help is VERY APPRECIATED!!!! Thanks!!!

Connection refused to MongoDB errno 111

I am using CentOS 7 and I have to ensure that ports 2888 and 3888 are open.

I read [this article](http://wiki.centos.org/HowTos/Network/IPTables) but this did not work because on CentOS 7 OS there is no `iptables save` command.

Someone told me that the above URL is not valid for CentOS 7. and I should follow [this](https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/7/html/Security_Guide/sec-Using_Firewalls.html). 
But this article is not clear to me on exactly what command I need to execute.

I also found 

    firewall-cmd --zone=public --add-port=2888/tcp 

but this does not survive reboots.

So how can I open the ports and make it survive reboots?

Open firewall port on CentOS 7

I installed CentOS 7 with minimal configuration (os + dev tools). I am trying to open 80 port for `httpd` service, but something wrong with my iptables service ... what&#39;s wrong with it? What am I doing wrong? 


    # ifconfig/sbin/service iptables save
    bash: ifconfig/sbin/service: No such file or directory


    # /sbin/service iptables save
    The service command supports only basic LSB actions (start, stop, restart, try-restart, reload, force-reload, status). For other actions, please try to use systemctl.

    # sudo service iptables status
    Redirecting to /bin/systemctl status  iptables.service
    iptables.service
       Loaded: not-found (Reason: No such file or directory)
       Active: inactive (dead)
    
    # /sbin/service iptables save
    The service command supports only basic LSB actions (start, stop, restart, try-restart, reload, force-reload, status). For other actions, please try to use systemctl.
    
    # sudo service iptables start
    Redirecting to /bin/systemctl start  iptables.service
    Failed to issue method call: Unit iptables.service failed to load: No such file or directory.



How can I use iptables on centos 7?

git 1.7.1

`git show &lt;hash&gt;:&lt;file&gt;` gives me the file based on the commit hash provided

I am trying to figure out how to bet the file of the previous commit before the one who&#39;s hash I have.

I know I can always use the `log` to get all hashes and figure out the one i need but that&#39;s not a good solution in my case as I am trying to minimise the number of commands I need to do for performance issues.

Was wondering if there is a simple way.

GIT get the commit hash prior to a specific commit

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

Content Type	Original Author	Original Content on Stackoverflow
Question	user3809096	View Question on Stackoverflow
Solution 1 - Php	lpaseen	View Answer on Stackoverflow
Solution 2 - Php	Sudhir Gaurav	View Answer on Stackoverflow

nohup:ignoring input and appending output to 'nohup.out'

Php Problem Overview

Php Solutions

Solution 1 - Php

Solution 2 - Php

Get value from one Optional or another

Use adb over tcpip in Android Studio?

Attributions