If Totem , the default movie player does not play vcds properly , showing file permission errors , then try : 1. SMPlayer Install from synaptic : sudo apt-get install smplayer 2. mplayer Install from synaptic : sudo apt-get install mplayer 3. KPlayer Install from synaptic : sudo apt-get install kplayer To play from terminal… Read More »
Google Chrome has problem displaying hindi/unicode and other Indian language fonts. For example bold hindi fonts might be displayed as square boxes. http://code.google.com/p/chromium/issues/detail?id=32109 http://code.google.com/p/chromium/issues/detail?id=21320 It is some kind of font selection bug. Lets try fixing it. 1. You may want to install the packages ttf-devanagari-fonts and ttf-indic-fonts. Also get that mangal.ttf thing from windows or… Read More »
VCDs that are played on vcd players often contain the video in dat format. The dat format is internally mpeg only but has some additional header information attached. So the mpeg portion has to be ripped off to get the mpeg format. Once converted to mpeg format, it can be processed inside any video editor…. Read More »
Resizing images Web applications often need to work with images like pictures of users or photos etc. So the need to resize images comes up when creating thumbnails for example or compressing images for storage. The default library to handle image operations in php is GD. It can be used to resize images. GD vs… Read More »
Auto mount partitions On linux the hard drive partitions are generally not mounted at boot. Clicking on the drive icon inside a file manager like nautilus or dolphin mounts them first and then shows the files. But it is possible to get the drives mounted right at boot. The configuration file in this case is… Read More »
The php_flag directive can be used to set options that are specific to the php interpreter, directly from the .htaccess file. It is a good way to setup parameters across entire site, without having to repeat them in each php script or code. The following code, turns off the register globals setting in php. <IfModule… Read More »
As you all know Ruby is one of the most popular programming language on the web. It is recommended to install ruby 1.9.2 instead of 1.8.x I tried to install ruby from the package manager on Ubuntu, but ruby 1.9.2 is not there in the repo. So, I am going to show you how to… Read More »
System load System load is a measure of how busy the system is running the processes. Higher system load simply means more processes are running and more are waiting to be run. When coding php applications, it sometimes is useful or necessary to find the current load on the server/system. For example if you want… Read More »
Path Info Urls When using path info data , the urls of codeignitor apps or your custom mvc frameworks looks something like this example.com/index.php/controller/method/param1/param2 or example.com/controller/method/param1/param2 The path info data can be used to specify which class and method should be invoked on server application. Forward slash in parameter Sometimes it might so happen that… Read More »
Apache mod expires mod expires is an Apache module that can send additional expiry information about a server file to a browser. If the expiry date is set to a far future date, then the browser will fetch the file from its cache on next request and will not contact the server. This will speed… Read More »
When you install Ubuntu on your system, a common issue that pops up is that partitions other than the root partition are not writable by non-root users. The same thing happens when you add an extra disk drive to your system. The disk or partition can be read through file managers like Nautilus or Dolphin… Read More »
Install Xdebug Install the packages from synaptic package manager sudo apt-get install php5-dev php5-xdebug Configure php to use xdebug extension Locate the path to xdebug.so file martin@martin-dev:/$ find / -name 'xdebug.so' 2> /dev/null /usr/lib/php5/20060613/xdebug.so An alternative command to find the xdebug.so file is using dpkg and grep as follows $ dpkg -L php5-xdebug | grep… Read More »
This page http://httpd.apache.org/docs/2.2/howto/cgi.html describes how to give each user his own cg-bin directory. The following lines should be added to the Apache configuration file http.conf : <Directory /home/*/public_html/cgi-bin> Options ExecCGI SetHandler cgi-script </Directory> Along with this there are some more points to be kept in mind. If you .htaccess file has a section like this… Read More »
The PATH-INFO is the extra path data that follows the name of a script (or servlet) in the URL. Its different from query string. Here is a classic example: https://www.examples.com/index.php/some/path?a=b Now, over here we are actually invoking the script index.php only. However also providing some path-info data “/some/path”, which is then followed by the query… Read More »
information_schema The following query will list out the foreign keys in mysql. It finds it out from the information_schema database. select concat(table_name, '.', column_name) as 'foreign key', concat(referenced_table_name, '.', referenced_column_name) as 'references' from information_schema.key_column_usage where referenced_table_name is not null; The output is a clean table listing out all foreign keys from all databases +———————–+————-+ |… Read More »
The innodb storage engine supports foreign keys in Mysql. To create foreign keys in phpmyadmin : 1. Convert both tables into innodb, if they are not already. 2. View the structure of the table which will have a foreign key. Make the referencing field an INDEX. 3. Now come back to structure view and click… Read More »
Views and mysqldump A little back I tried to backup a database from my webhost and restore it on my localhost mysql. It had a few views. The import of the sql file seemed to work fine. But on accessing the views in phpmyadmin mysql gave the error : #1449 – There is no 'projects'@'localhost'… Read More »
Gnome MDB viewer is a simple tool to open and view mdb (microsoft access database) files on Ubuntu or Linux Mint. It shows the database structure and the data in it
While creating a table a particular column / field can be made autoincrement as : CREATE TABLE students ( id INTEGER NOT NULL GENERATED ALWAYS AS IDENTITY (START WITH 1, INCREMENT BY 1), name VARCHAR(24) NOT NULL, address VARCHAR(1024), CONSTRAINT primary_key PRIMARY KEY (id) ) ; The value of an autoincrement column increments automatically with… Read More »
To go back to the previous page the superglobal variable $_SERVER can be used. $_SERVER[‘HTTP_REFERER’] has the link to the previous page. So to redirect simply : // Method to go to previous page function goback() { header("Location: {$_SERVER['HTTP_REFERER']}"); exit; } goback();