Arpan Dubey

Method Chaining in PHP

Method Chaining is a technique where different methods are chained together into single instruction. For example, $dao->execute()->prepare($var) ; The above method of chaining will work as long as the functions called will return an object to chain on. For example, object->function_3(); (object-function_2())->function_3();      // function_3 still gets an obj ( ( object->function_1() )->function_2() )->function_3();   // finally The class definition for this is: <?php /** method chaining class */ class myclass{ public $var ; public function_1(){ echo __FUNCTION__"\n" ; return $this; }      public function_2(){ echo __FUNCTION__"\n" ; return $this; }      public function_3(){ echo __FUNCTION__"\n" ; return $this; } } All the function above returns $this and can be chained.…
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Bootstrap CSS3 Class LIst

Basic Bootstrap Classes .container sets fixed width to an element (which changes depending on a screen size to other fixed values, so it's still responsive) on all screen sizes except xs - on xs, the width is calculated automatically (this behaviour can be changed) a fixed width responsive website should be wrapped in .container (or just the content without menu, whatever - it's up to you) .container can't be nested! .container-fluid sets 100% width, margin-left and margin-right: auto, padding-left and padding-right: 15px a full screen website should be wrapped in .container-fluid .container-fluid can't be nested! .row creates horizontal groups of columns (which usually have width classes, see below) must be…
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How to disable php session() cookie ?

Why would you want to do that? Is it because you are executing an application in php and its not working. Sometimes you need to refresh the page twice to get it work, or maybe its only working once and then it would work only after executing the cookie cleaner? Solution : Add the following to your .htaccess file: SetEnv session.use_cookies='0'; Of, before you call session_start(), add the following to your php files: ini_set('session.use_cookies', '0'); To permanently disable cookies for session on the server ( not recommended !), add the following to your php.ini file : session.use_cookies = 0 Comments welcome. Regards
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fatal error: bcm_host.h: No such file or directory compilation terminated

fatal error: bcm_host.h: No such file or directory compilation terminated system is LInux opensuse 13.2 . I encoutered this problem while compiling mplayer. It would fail to compile. I disabled many extensions but it would not solve the problem. There is very little information available about this file online. Mostly its about the discussion of Raspberry. I tried changing the reference to the file in source code, but compilation fails again. Solution  : Download the mplayer source again and compile it afresh. It will automatically download the latest version of ffmpeg and all would go well. Comments warmly welcomed. Regards.
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Command for rsync for ssh running on non-default port no 22

Rsync is great unix tool to sync files between systems. It has inbuilt compression much needed for reducing network load, transfers in acrhieve mode so that permission are preserved. However, the best feature of rsync is that it transfers in delta mode. That is, compares remote and local files, and only transfers the files that are changes ! Awesome and cool for many years. However, due to security reasons I ran my ssh server on a remote system at a non standard port. Since port 22 is constantly bombarded with login attempts, it is a great security strategy to use a non default port. The command to run for rsync…
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How to secure SSH on Remote server ?

Simple strategies to secure ssh server. Ssh is perhaps the most secure remote shell around, and at the same time the most abused one too. I have like a thousand attempts on my servers on default ssh port no 22. The tries are mostly dictionary attacks and brute forcing. Default security of ssh to delay the logins and use of strong passwords usually suffice to tackle this. How attackers plan and execute a dictionary attack ? First of all "nmap" is used to check if port 22 is open and is serving, then script execute dictionary attack on the port. This attack may run for years trying out various passwords…
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Thinkpad touchpad with Linux

The touchpad is not performing as good as it used to do on LInux. Here is a small tweak that would make it behave better : Thinkpad W520, OpenSUSE 13.2 . Check if this package is installed on your system : xf86-input-synaptics-1.8.1-1.1.x86_64 The package name is <synaptics> and should be available with the package manager of your choice on all major linux platforms. The procedure should work with very little modification on Fedora, OpenSuse, Debian, Ubuntu, Arch and most other linux distributions and threir derivatives. Usually installed as default. Tweaks using the command line tools for a more sane mouse experience : Check the current settings of the touchpad. This…
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VirtualBox guest RDP authenticiation

RDP authentication For each virtual machine that is remotely accessible via RDP, you can individually determine if and how client connections are authenticated. For this, use VBoxManage modifyvm command with the --vrdeauthtype option; see the section called “VBoxManage modifyvm” for a general introduction. Three methods of authentication are available: The "null" method means that there is no authentication at all; any client can connect to the VRDP server and thus the virtual machine. This is, of course, very insecure and only to be recommended for private networks. The "external" method provides external authentication through a special authentication library. VirtualBox ships with two such authentication libraries: The default authentication library, VBoxAuth, authenticates against user credentials of the hosts.…
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openSuse 13.2 : The simple solutions

I installed openSuse 13.2 yesterday. Some minor issues as usual but all seems stable and good. Sharing my experience so that you can save your time and set up openSuse 13.2 on your thinkpad quicker. I am using Lenovo Thinkpad W520 with Nvidia Optimus on a FHD display. Three major components that have configuration problem peculiar to Lenovo Thinkpad are the Palm Detection Failure of the touchpad, flickering screen brightness control and nvidia optimus display adapter. Thinkpad Touchpad Settings I always set the touchpad speed of thinkpad and enable palm detection so that my mouse cursor doesn't fly all over the screen. # synclient PalmDetect=1 # synclient PalmMinWidth=8 # synclient…
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