Sunday, November 4, 2012

Windows 8 Extended Attributes Are Inconsistant Error - Solved/Fix

If you have upgraded to Windows 8 from Windows 7 then you will be seeing this error frequently.

Pretty quickly I found every program that tried to elevate to Administrative privileges had this problem. The UAC prompt to click Yes/No appeared very briefly then was rapidly replaced with this error message.

So I restarted the PC and pressed F8 to enter safe mode. I then logged in with a local administrator account and as safe mode is free of UAC prompts could happily set User Account Control Settings to Never Notify

Warning! Using this setting is not recommended.

Restarting back into regular Windows I could now launch programs as admin. I launched a command prompt as Admin and reset UAC back to the previous setting.

Saturday, November 3, 2012

Speed up the Javascript file loading in your site

There is a nice technique to reduce the amount of calls your browsers has to make to the server. This will be every image, every css and every JavaScript file included in the webpage. Each time you want to load in one of these elements you will be sending a request to the server which will return the requested object known as a HTTP request.
Reduce Page Loading Time With PHP

Each one of these uses up time on your page loading, so to reduce page load all you have to do is reduce the amount of calls being made. But what if you want to organise you JavaScript files, jquery file, general file, application file and page file. There could be upto 4 requests for some javascript for the page.

It is possible in PHP to combine these JavaScript files together and trick the browser into thinking they are just one JavaScript file, therefore reducing the amount of calls being made to the server. This is done by reading the JavaScript with PHP then changing the header to JavaScript like the example below.

Create a PHP file and use the readfile function to bring in your Javascript files then change the header to Javascript and the server will treat this page as Javascript.

header(‘Content-type: text/javascript’);

Monday, May 28, 2012

How do I configure website .htaccess only GoogleDocs Document Viewer can read the files

Open your .htaccess file in the root folder of the website. Add the below set of lines to it.

RewriteEngine on
RewriteCond %{HTTP_REFERER} !^http(s)?:// [NC]
RewriteCond %{HTTP_REFERER} !^http(s)?://(www\.)? [NC]
RewriteRule \.(doc)$ - [NC,F,L]

Using the google document embedded viewer
< iframe frameborder="0" src="" style="height: 500px; width: 600px;">

If we use the above hotlink protection then the url http:// is not accessible directly. Only Google Document viewer can access the file.


Saturday, May 19, 2012

Facebook India, Hyderabad - Address and Location

View Larger Map

Facebook India,
Building No. 14,
MindSpace IT Park,
Hi-Tec City,
AP 500 081,

Thursday, March 15, 2012

PHP - Coding Tips #2

  • If a method can be static, declare it static. Speed improvement is by a factor of 4.
  • echo is faster than print.
  • Use echo’s multiple parameters instead of string concatenation.
  • Set the maxvalue for your for-loops before and not in the loop.
  • Unset your variables to free memory, especially large arrays.
  • Avoid magic like __get, __set, __autoload
  • require_once() is expensive
  • Use full paths in includes and requires, less time spent on resolving the OS paths.
  • If you need to find out the time when the script started executing, $_SERVER[’REQUEST_TIME’] is preferred to time()
  • See if you can use strncasecmp, strpbrk and stripos instead of regex
  • str_replace is faster than preg_replace, but strtr is faster than str_replace by a factor of 4
  • If the function, such as string replacement function, accepts both arrays and single characters as arguments, and if your argument list is not too long, consider writing a few redundant replacement statements, passing one character at a time, instead of one line of code that accepts arrays as search and replace arguments.
  • It’s better to use select statements than multi if, else if, statements.
  • Error suppression with @ is very slow.
  • Turn on apache’s mod_deflate
  • Close your database connections when you’re done with them
  • $row[’id’] is 7 times faster than $row[id]
  • Error messages are expensive
  • Do not use functions inside of for loop, such as for ($x=0; $x < count($array); $x) The count() function gets called each time.
  • Incrementing a local variable in a method is the fastest. Nearly the same as calling a local variable in a function.
  • Incrementing a global variable is 2 times slow than a local var.
  • Incrementing an object property (eg. $this->prop++) is 3 times slower than a local variable.
  • Incrementing an undefined local variable is 9-10 times slower than a pre-initialized one.
  • Just declaring a global variable without using it in a function also slows things down (by about the same amount as incrementing a local var). PHP probably does a check to see if the global exists.
  • Method invocation appears to be independent of the number of methods defined in the class because I added 10 more methods to the test class (before and after the test method) with no change in performance.
  • Methods in derived classes run faster than ones defined in the base class.
  • A function call with one parameter and an empty function body takes about the same time as doing 7-8 $localvar++ operations. A similar method call is of course about 15 $localvar++ operations.
  • Surrounding your string by ‘ instead of ” will make things interpret a little faster since php looks for variables inside “…” but not inside ‘…’. Of course you can only do this when you don’t need to have variables in the string.
  • When echoing strings it’s faster to separate them by comma instead of dot. Note: This only works with echo, which is a function that can take several strings as arguments.
  • A PHP script will be served at least 2-10 times slower than a static HTML page by Apache. Try to use more static HTML pages and fewer scripts.
  • Your PHP scripts are recompiled every time unless the scripts are cached. Install a PHP caching product to typically increase performance by 25-100% by removing compile times.
  • Cache as much as possible. Use memcached – memcached is a high-performance memory object caching system intended to speed up dynamic web applications by alleviating database load. OP code caches are useful so that your script does not have to be compiled on every request
  • When working with strings and you need to check that the string is either of a certain length you’d understandably would want to use the strlen() function. This function is pretty quick since it’s operation does not perform any calculation but merely return the already known length of a string available in the zval structure (internal C struct used to store variables in PHP). However because strlen() is a function it is still somewhat slow because the function call requires several operations such as lowercase & hashtable lookup followed by the execution of said function. In some instance you can improve the speed of your code by using an isset() trick.
    1.if (strlen($foo) < 5) { echo "Foo is too short"; }
    1.if (!isset($foo{5})) { echo "Foo is too short"; }
    Calling isset() happens to be faster then strlen() because unlike strlen(), isset() is a language construct and not a function meaning that it’s execution does not require function lookups and lowercase. This means you have virtually no overhead on top of the actual code that determines the string’s length.
  • When incrementing or decrementing the value of the variable $i++ happens to be a tad slower then ++$i. This is something PHP specific and does not apply to other languages, so don’t go modifying your C or Java code thinking it’ll suddenly become faster, it won’t. ++$i happens to be faster in PHP because instead of 4 opcodes used for $i++ you only need 3. Post incrementation actually causes in the creation of a temporary var that is then incremented. While pre-incrementation increases the original value directly. This is one of the optimization that opcode optimized like Zend’s PHP optimizer. It is a still a good idea to keep in mind since not all opcode optimizers perform this optimization and there are plenty of ISPs and servers running without an opcode optimizer.
  • Not everything has to be OOP, often it is too much overhead, each method and object call consumes a lot of memory.
  • Do not implement every data structure as a class, arrays are useful, too
  • Don’t split methods too much, think, which code you will really re-use
  • You can always split the code of a method later, when needed
  • Make use of the countless predefined functions
  • If you have very time consuming functions in your code, consider writing them as C extensions
  • Profile your code. A profiler shows you, which parts of your code consumes how many time. The Xdebug debugger already contains a profiler. Profiling shows you the bottlenecks in overview
  • mod_gzip which is available as an Apache module compresses your data on the fly and can reduce the data to transfer up to 80%.
  • Do use single quotes over double quotes.
  • Do use switch over lots of if statements
  • Do avoid testing loop conditionals with function tests every iteration eg. for($i=0;i<=count($x);$i++){…
  • Do use foreach for looping collections/arrays. PHP4 items are byval, greater than PHP5 items are byref
  • Do consider using the Singleton Method when creating complex PHP classes.
  • Do use POST over GET for all values that will wind up in the database for TCP/IP packet performance reasons.
  • Do use ctype_alnum,ctype_alpha and ctype_digit over regular expression to test form value types for performance reasons.
  • Do use full file paths in production environment over basename/fileexists/open_basedir to avoid performance hits for the filesystem having to hunt through the file path. Once determined, serialize and/or cache path values in a $_SETTINGS array. $_SETTINGS["cwd"]=cwd(./);
  • Do use require/include over require_once/include_once to ensure proper opcode caching.
  • Do use tmpfile or tempnam for creating temp files/filenames
  • Do use a proxy to access web services (XML or JSOM) on foreign domains using XMLHTTP to avoid cross-domain errors. eg.<–>XMLHTTP<–>
  • Do use error_reporting (E_ALL); during debug.
  • Do set Apache allowoverride to “none” to improve Apache performance in accessing files/directories.
  • Do use a fast fileserver for serving static content (thttpd).,
  • Do serialize application settings like paths into an associative array and cache or serialize that array after first execution.
  • Do use PHP output control buffering for page caching of heavilty accessed pages
  • Do use PDO prepare over native db prepare for statements. mysql_attr_direct_query=>1
  • Do NOT use SQL wildcard select. eg. SELECT *
  • Do use database logic (queries, joins, views, procedures) over loopy PHP.
  • Do use shortcut syntax for SQL insers if not using PDO parameters parameters. eg. INSERT INTO MYTABLE (FIELD1,FIELD2) VALUES ((“x”,”y”),(“p”,”q”));


PHP - Coding Tips #1

In PHP there are so many ways to perform the same task. Normally developers are using the way which is most comfortable for them or which they are more aware of.
  1. echo is more faster than print. Both functions are used for the same thing but echo is the language construct which return nothing, which print will return 0 or 1 based on success or failure.
  2. include_once is more costly than include statement. Because it have to search for class definition you are trying to include is already included or not?
  3. Always use single quotes for long strings instead of double quotes. Because in double quotes it will search for php variable to evaluate them. So in this case, echo ‘This is long string’ . $name is faster then echo “This is long string $name”. But from above both echo ‘This is long string’ , $name, is faster because it does not require any string manipulation.
  4. Don’t use for( $i=0; $i < count ($ names );$i++){…} instead of this use $size = count($names); for($i=0; $ i<$ size;$i++){…}. The first method will call count function on each iteration of for loop, while in second iteration count function is being called only once.
  5. If you can declare a method as static then let it be, because its 33% more faster than member functions.
  6. If you can solve your problem without using regular expression then don’t use it. Regular expression are slower then their php counterparts. For example use str_replace instead of preg_replace.
  7. Try to minimize relative paths for files inclusion. For relative path inclusion it will search for default include path then current directory then so on. So file search in that case may take more time. Better practice is to declare the constant called WEB_ROOT which defines the root.
  8. Identical operator (===) is faster than (==) operator as identical operator will include type checking also. So If( 1 == ’1′) will return true, If( 0 == ”) will return true while if you use identical operator both this conditions If( 1 === ’1′) and If(0 === ”)  will return false. So it is recommended to use identical operator when you are going to use some boolean variables for deciding the flow/control of your application.
  9. Don’t use short tags and try to using , It can create a problem for you if you are going to deploy your application on another server.
  10. Don’t use or relay on register_globals or magic quotes and read and configure your php.ini settings carefully.

Wednesday, February 22, 2012

How to check htaccess and mod_rewrite is enabled ?

1. Open a blank notepad document

2. Copy and paste the following code into the blank notepad

You are not using mod_rewrite - Try LINK2';} elseif($_GET['link']==2){echo'Congratulations!! You are using Apache mod_rewrite';} else{echo 'Linux Apache mod_rewrte Tutorial';} ?>

How To Test mod_rewrite in Apache Linux ServerLINK 1 = LINK 1 Does NOT use Mod Rewrite. LINK 1 uses standard URL: rewrite.php?link=1
LINK 2 = LINK 2 - Yes, Uses Apache's Mod Rewrite using this URL:: link2.html

How this works: both links are for this same page, except they both are different. link one is without the mod_rewrite and link2 is using mod_rewrite. Link1 show the php file, with with mod_rewrite we are mascaraing the php file into a html file. you can use whatever type of extension you want, you can change it to .htm or .shtml etc... all you have to do is to make sure you also chang it in the .htaccess file
NOTE: when you click on LINK2, you should see a message that says: Congratulations!! You are using Apache mod_rewrite
500 ERROR: If you get a 500 Error, this means you made a typo or mistake creating the files OR you are not allowed to use .htaccess
404 ERROR: if you get a 404 error, then this means you do not have Mod_Rewrite on this server.

3. Now Save the file as "rewrite.php"

4. Now create a file called .htaccess - to make this type of file, open another blank notepad document

5. Copy and paste the following code into the .htaccess file:
RewriteEngine On
RewriteRule ^link([^/]*).html$ rewrite.php?link=$1 [L]

6. Save as ".htaccess" (if you are using notepad as I am, make sure to put quotes in between .htaccess example: ".htaccess" otherwise, notepad will create a file called .htacces.txt and we don't need the .txt at the end only .htaccess)

7. Now upload these two file into a new directory in your site. for example: test/

8. Open the rewrite.php file with your browser to the location you just uploaded. for example:

9. you should see two links, LINK1 and LINK2 Click on LINK1 and the same page will display.

10. Now click on LINK2 and the same page will display with the a mod_rewrite message. If it doesnt you either did something wrong. Check your steps. If you checked your steps, refresh your browser, and if refreshing doesnt work, then you dont have mod_rewrite enabled or you dont have permission to run .htaccess files on your website. talk to your web hosting company to make sure they allow apache .htaccess - Some hosting companies do not allow .htaccess because some people take advantage of this feature, so many web hosting companies block their users from using. so check with them

If you get a 500 Error, then you do not have mod_rewrite enabled in your server.

Cron - Warning: failed to open stream [Solved]

While setting up a cron job from cPanel or Simple Control Panel you will encounter Warning messages like failed to open stream. But the file may works perfectly from the browser. 

Error like this,
Warning: main(home/default/cron.php): failed to open stream: No such file or directory in /home/abc/ on line 1

This is because, the script not running from the current directory. For solving the issue you need to initialize the current directory.

Add the below code to the start of your cron script file. This will change to current directory and hence all the issues will be solved.

  chdir( dirname ( __FILE__ ) );

Saturday, January 28, 2012

Sorting Product Category Widget - WP E-Commerce Plugin Wordpress

Wordpress WP E-Commerce Plugin, There is a widget called Product Category Widget which lists all the product categories. During the site development you may have a lot of categories and nested categories then it will be difficult to sort the list. So here I'm helping you with a bit of code which will sort the products in the widget.

Method 1:

Edit the file :  /wp-content/plugins/wp-e-commerce/wpsc-widgets/category_widget.php
Add the below highlighted code to your php file.

$instance_categories = get_terms( 'wpsc_product_category', 'hide_empty=0&parent=0&orderby=name&order=ASC');
 function subval_sort($a,$subkey) {
            foreach($a as $k=>$v) {
                $b[$k] = strtolower($v[$subkey]);
            foreach($b as $key=>$val) {
                $c[] = $a[$key];
            return $c;
            $newArray = array();
            $tempI = $i;
            foreach($instance_categories as $key=>$value)
                $newArray[$i]['term_id'] = $value->term_id;
                $newArray[$i]['name'] = $value->name;
                $newArray[$i]['slug'] = $value->slug;
                $newArray[$i]['term_group'] = $value->term_group;
                $newArray[$i]['term_taxonomy_id'] = $value->term_taxonomy_id;
                $newArray[$i]['taxonomy'] = $value->taxonomy;
                $newArray[$i]['description'] = $value->description;
                $newArray[$i]['parent'] = $value->parent;
                $newArray[$i]['count'] = $value->count;
                $newArray[$i]['sort_order'] = $value->sort_order;
            $i = $tempI;
            $newArray = subval_sort($newArray,'name');
            $xyz = 0;
            $instance_categories = array();
            foreach($newArray as $key=>$value)
                $instance_categories[$xyz] = (object) $value;   

                foreach($instance_categories as $categories){

                    $instance['categories'][$categories->term_id] = 'on';

Method 2:  
You can use the below query also to fetch categories and can use it recursively for sub-categories.

    $results =$wpdb->get_results("SELECT name, slug
    FROM wp_term_taxonomy AS wtt
    JOIN wp_terms AS wt ON wt.term_id = wtt.term_id
    WHERE wtt.taxonomy = 'wpsc_product_category'
    AND wtt.parent =$category_id");

    foreach($results as $key=>$value)

  • name; ?>

  • }

Wednesday, January 25, 2012

PHPMailer with GoDaddy SMTP email script - Resolved.

Here is the working script for PHP Mailer in GoDaddy Hosting,



$email = '';
$firstName = 'Aravind';

$mail             = new PHPMailerR();
$mail->SMTPDebug                      = 1;                 
$mail->SMTPAuth                           = SMTP_AUTH;                $mail->Host                                   = SMTP_HOST;
$mail->Port                                    = 25;
$mail->Username                           =  SMTP_USERNAME;
$mail->Password                            = SMTP_PASSWORD;
$mail->Subject    = "Welcome to AravindNC.IN";
$mail->AltBody    = "To view the message, please use an HTML compatible email viewer!";
$mail->MsgHTML('This is a test.');
$mail->AddAddress($email, 'Aravind NC');

Share this if you got it working.

Tags : PHPMailer with GoDaddy SMTP email server Script working,

Monday, January 23, 2012

Arshaw Full Calendar - Timezone fix

When we are pulling date from the server having UTC, it may display in local timezone format in Arshaw's Full Calendar. This is due to the misconfiguration in the full calendar function we are using. 

There is a constant for avoiding the timezone ie. ignoreTimezone, When parsing ISO8601 dates, whether UTC offsets should be ignored while processing event source data. The default is true, which means the UTC offset for all ISO8601 dates will be ignored. For example, the date "2008-11-05T08:15:30-05:00" will be processed as November 5th, 2008 at 8:15am in the local offset of the browser.

The below sample code shows how to use the ignoreTimezone in fullcalendar to avoid the local time constraint.

            eventSources: [
                ignoreTimezone: true
// For ignoring timezone
                left: 'prev,next today',
                center: 'title',
                right: 'month,agendaWeek,agendaDay'
            editable: false,

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