# cd /home/photos
# vim compress.sh

1
2
3
4

for img in `ls *.JPG`
do
convert -quality 40% $img my-$img
done

or
Simply copy the script and paste into your image folder. and run the script in your terminal

# chmod 777 compress.sh
# ./compress.sh

This script will reduce the size of image into approximately 300 KB .
Reference : IBM Website

Checking GCC compiler
GCC comes with all Linux flavors by default . To check the version of your GCC , type this command in your terminal

root@Ubuntu:/home/anthoniraj# gcc  –version
gcc (Ubuntu 4.4.1-4ubuntu9) 4.4.1
Copyright (C) 2009 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

By default only C compiler will be there in GCC , you can install C++ support by typing this command in Ubuntu

#sudo apt-get install build-essential

Developing C Program
You can use your favorite editor or IDE like Netbeans or Eclipse to develop the C and C++ programs. I am using VIM the simple and king of all editor for developing these programs. Now simply we can write one C program for finding factorial of a given number.
#vim factorial.c [ file type is .c ]

#include<stdio.h>
int main()
{
int n , i ;
unsigned long int  res = 1;
printf("\nEnter the number to find the factorial:");
scanf("%d" , &n );
for(i = 1 ; i <= n ; i++)
{
res *= i;
}
printf("\n The factorial value of %d is %lu\n" , n, res);
return 0;
}

Compiling and Running
To compile c program , use gcc with file name

#gcc factorial.c
#./a.out [Default buffer for output]
Enter the number to find the factorial: 5
The factorial value of 5 is 120
or
#gcc factorial.c -o fact.out
#./fact.out [customized file for output]

Note :

1. There is no void keyword in GCC ,
2. Use int instead of void and also use return 0 .

Developing C++ Program
Now I am going to write C++ for the same factorial method.
#vim factorial.cpp [File Type is cpp]

#include <iostream>
using namespace std;
int main()
{
int n ;
unsigned long int  res = 1;
cout << "\nEnter the number to find the factorial:" << endl;
cin << n ;
for(int i= 1 ; i <= n ; i++)
{
res *= i;
}
cout <<"The factorial value of " <<"is " << endl;
return 0;
}

Compiling and Running
To compile c program , use gcc with file name

#g++ factorial.cpp
#./a.out [Default buffer for output]
Enter the number to find the factorial: 5
The factorial value of 5 is 120
or
#g++ factorial.cpp -o fact.out
#./fact.out [customized file for output]

Note :

1. Dont use .h for header files
2. Use name space for header-file functions

anthoniraj@Ubuntu:~/sample$ ls

sam.txt  uploads  users.csv  users.txt

2. Display the file and folder with privileges , ownership , and size

anthoniraj@Ubuntu:~/sample$ ls -l
total 16
-rw-r–r– 1 anthoniraj anthoniraj    5 2010-04-08 06:49 sam.txt
drwxrwxrwx 2 anthoniraj anthoniraj 4096 2010-03-26 08:49 uploads
-rw-r–r– 1 anthoniraj anthoniraj  140 2010-04-07 10:33 users.csv

-rw-r–r– 1 anthoniraj anthoniraj  145 2010-04-07 10:32 users.txt

3. Display all files including hidden files

anthoniraj@Ubuntu:~/sample$ ls -a
.  ..  sam.txt  uploads  users.csv  users.txt

ls command output

4. Display the folder content recursively

anthoniraj@Ubuntu:~/sample$ ls -R

.:

sam.txt  uploads  users.csv  users.txt
./uploads:

cs1999.pdf  kavidhai.pdf  New Text Document.txt  Sample.txt

5. Display the inode or index number of each file

anthoniraj@Ubuntu:~/sample$ ls -i
331894 sam.txt  336568 uploads  331901 users.csv  331902 users.txt

# man command-name

This will display the information like name , syntax , description , example , author of the particular command. User can also use some options like  “-f” for short description and “-k” for displaying commands based on the keyword.
Regular Usgae
1. Displaying Manual or Help Page

#man find

Manual Page for Find Command

2. Getting Short Description

#man  -f  ifconfig

Short Description of ifconfig

3.Getting List of commands using Keyword
If you want to know about the commands for network operations ,  you do not know all the Linux networking commands , In this situaltion “man -k” option will help you. Type the keyword “network” with option “-k” in man command , it will display all the commands matching the keyword like network.

#man -k “network”

List of Network Commands

4. Converting Manual Page into Portable Format [ Text , PDF , PS ]

The default format of the man pages are in troff [ Text Formatting System]. We can convert troff format to text pdf or ps format using man with following options
i) For Text File conversion

# man ls | col -b > lstext.txt

ii) For PDF or PS conversion

#man -t ls > lsps.ps
#man -t ls | ps2pdf – > lstext.pdf

Recently  , i installed drupal content management system to my yahoo small business web hosting server.  Everything was good except sending email. Every time when i create new user i got this error

Unable to send e-mail. Please contact the site administrator if the problem persists.

I googled so many pages , but i could not find any solution , finally i changed one configuration in my drupal CMS , i.e., I changed my personal email id to yahoo domain email id in site configuration page of druapl. now email system  is perfectly working  . . .

Steps

1. Login with Drupal using admin privileges
2. Select the option “Site Configuration” in Admin Menu
3. Select “Site Information” under this.
4. In Email Text Box change your personal address [ sam@gmail.com ] to yahoo domain address [ sam@openpeta.com ]
5. Save your configuration

Thats It

Note : When you purchase yahoo small business plan , yahoo will provide one email id with your domain [ like anto@openpeta.com ] . here anto is the user name and openpeta.com is the domain name  , so use this one in site information email text field .

How to draw line, circle , or 2D graphics in Linux Using C or C++?

I was searching Internet and found some softwares for developing graphics applications in Linux. that softwares are listed here

1. GTK+   – Gnome Tool Kit
2. QT  -  The X toolkit
3. SVGALIB   [ #include<vgagl.h> ]
4. libgraph [ #include<graphics.h> ]

GTK and QT are simple and used for high level Graphical User Interface [ GUI ] development. SVGALIB and libgraph is used for 2D graphics in Linux .  the syntax and functions are some what different for beginners  [specially the user from windows ] but most of users familiar with windows graphics.h header file in C and C++ , so we can move for libgraph which is exact one for windows graphics user . libgraph is an implementation of the Turbo C graphics API (graphics.h) on GNU/Linux using SDL [ Simple Direct Media Player ]. The library requires SDL for primitive graphics and SDL. First you need to install the following dependency packages using synaptic package manager in Ubuntu Linux to develop the graphics applications properly.

• SDL Library

Installing SDL Library

• GUILE – GNU’s Ubiquitous Intelligent Language for Extension

GUILE Installation

• After installing these two packages , download the libgraph and install in your system

#sudo su

#tar -xzvf libgraph-1.0.2.tar.gz

#cd libgraph-1.0.2

#make

# make install

For better understanding , watch this video given here ….

1. Open your favorite text editor and type the following code

1
2
3
4
5
6
7
8
9
10
11
12
13

#include "stdio.h"
#include "graphics.h"
int main()
{
int gd=DETECT, gm=VGAMAX;
initgraph(&gd,&gm, 0);
moveto(0, 0);
setcolor(4);
rectangle(50,50,500,200);
while(!kbhit());
closegraph();
return 0;
}

2. Now compile the program with lgraph library

#gcc line.c -lgraph -o output

#./output

If you get any error in this line like

./output: error while loading shared libraries: libgraph.so.1: cannot open shared object file: No such file or directory

Do the following

sudo cp /usr/local/lib/libgraph.* /usr/lib

3. Now one new window will open , there you will get the output Rectangle in Red color.

Output Window

The advantage of libgraph is very easy to remember the syntax  [ all functions are same as turbo c graphics.h ] . still if you are facing any problem to develop graphics applications using this , send your problems through comment page of this post.

1. PHP Basics
   • PHP Simple Program Structure
   • String Handling
   • Array Manipulation
   • Scope of Variables
   • Constant in PHP
2. PHP Basics – Conditional Statements
   • Simple If Condition
   • If-Else Condition
   • Nested If-Else
   • Alternate Syntax for If-Else in PHP
3. Looping Statements
   • while loop
   • do-while loop
   • for loop
4. PHP Cookie – Simple Example
5. Server Side Validation
6. File Handling in PHP
7. File Uploading in PHP
8. Database Connectivity [ PHP and MySQL]
   • Simple Login Form with MySQL Database
   • MySQL Insert Query with PHP
   • MySQL Select Query with PHP

   Post your valuable comments and suggestions about this article  ………

Object Serialization

Object Serialization is the process of converting object into stream of bytes which would be transferred via network. In other end the stream of bytes would be converted into original object , this process is called object de-serialization. The stream of bytes will be stored into a file in local disk after serialization.Now lets take small review about classes and methods used for Serialization and De-serialization process.

Package Name : java.io

Classes :

1. ObjectOutputStream
2. ObjectInputStream
3. FileOutputStream
4. FileInputStream

Methods :

1. Object readObject()
2. void writeObject(Object obj)

Example Program

Now lets create one Employee Object with some fields then we can apply the serialization concept.

1. Employee.java

package com.rmi.serial;
 
/*
 * Author :Anthoniraj.A
 * Date  : 30/06/09
 * Description : Program For Object Creation
 */
import java.io.Serializable;
 
public class Employee implements Serializable
{
    String name;
    String designation;
    double salary;
    int exp;
}

2.Employee Serialization

package com.rmi.serial;
/*
 * Author :Anthoniraj.A
 * Date  : 30/06/09
 * Description : Program For Object Serialization
 */
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.ObjectOutputStream;
import java.util.logging.Level;
import java.util.logging.Logger;
 
public class EmpSerializable
{
  Employee emp = null;;
  ObjectOutputStream oos = null;
 
  private void setValues()
  {
      emp = new Employee();
      emp.name = "Antony";
      emp.designation="AssistantProfessor";
      emp.salary =32000;
      emp.exp = 3;
  }
  private void serializeValues()
  {
        try
        {
          oos = new ObjectOutputStream(new FileOutputStream(new File("sample.ser")));
          oos.writeObject(emp);
          System.out.println("An Employee Object is serialized into sample.ser file");
        }
        catch (IOException ex)
        {
             ex.printStackTrace();
        }
        finally
        {
            try
            {
               oos.flush();
               oos.close();
            }
            catch (IOException ex)
            {
                Logger.getLogger(EmpSerializable.class.getName()).log(Level.SEVERE, null, ex);
            }
        }
  }
  public static void main(String a[])
  {
       EmpSerializable es = new EmpSerializable();
       es.setValues();
       es.serializeValues();
  }
 
}
 
OutPut
An Employee Object is serialized into sample.ser file

3.Employee DeSerialization

package com.rmi.serial;
/*
 * Author :Anthoniraj.A
 * Date  : 30/06/09
 * Description : Program For Object Deserialization
 */
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.ObjectInputStream;
 
public class EmpDeserializable
{
  ObjectInputStream ois = null;
  private void getValues()
  {
        try
        {
           ois = new ObjectInputStream(new FileInputStream(new File("sample.ser")));
 
           Employee em = (Employee) ois.readObject();
           System.out.println("Employee Name :" + em.name);
           System.out.println("Employee Designation :" + em.designation);
           System.out.println("Employee Salary :"+em.salary);
           System.out.println("Employee Experience :" + em.exp);
 
        }
        catch (Exception ex)
        {
           ex.printStackTrace();
        }
        finally
        {
            try
            {
                ois.close();
            }
            catch (IOException ex)
            {
               ex.printStackTrace();
            }
        }
     }
  public static void main(String a[])
  {
      new EmpDeserializable().getValues();
  }
}
 
output
Employee Name :Antony
Employee Designation :AssistantProfessor
Employee Salary :32000.0
Employee Experience :3

I’ve listed 5 of the best apps to hide, resize and do some funky stuff like translucency, all in the name of productivity. Check them
out:

1. KDE Window Resizer

One of the things I absolutely adore in KDE Window Resizer is how they handle window resizing and moving. You simply hold down the ALT key, just about grab the window from anywhere and you can move the window around. No need to grab the title bar. Perfect for situations  when the title bar is off screen due to change in screen resolution. To resize the window, just hold the ALT key and click and drag the right mouse button and the window starts resizing according to the movement.

2. Window Hider

Window Hider is a simple application that you can use for managing the open windows. It does two things – it can hide the window you want  by simply moving your mouse cursor to the corner or it can kill the application you specify.

You can give Window Hider a list of programs and a shortcut key then when you press that shortcut key it hides only those windows in your list. You can also activate hot corners on screen which hides all the programs in your list by simply moving the mouse cursor to the hot corner. Pretty cool.

3. Desk TopMost

So you have a lot of open windows? And you want to access the desktop icons? You could hit Win+D, but then you wouldn’t be able to return to the windows as they were opened, you would have restore the window from the taskbar yourself. Windows7 and Aero peek does an excellent job of it. In case you are not using Windows 7 or your computer doesn’t support the slick Aero Peek, you should try Desk Topmost. Just hit Ctrl + Alt + D and it provides you with a translucent overlay of your desktop over the open windows. After you are done, just right click anywhere and its gone.

4. Power Resizer

Allows you to mimic another one of the Windows 7 features, power resizer neatly fits your open windows to half screens or maximises them as you drag them to a screen edge or to the top of the screen. Simon covered it earlier here.

5. WindowTabs

WindowTabs attaches a small tab to the top of your windows. You can then drag tabs on top of each other to group them into tabbed windows. Use Alt + Right Arrow and Alt + Left Arrow to cycle through the tabs. Clicking on the tab with your mouse cursor willl take you to the tab as well. The application has a trial and a full version. While the trial version doesn’t have any time limits or nag screens, you would be limited to 3 tabs per group, which is not so bad of a deal.

How did those apps help you with your cluttered screen? Know of any more applications that fit the criteria? Or perhaps better alternatives to the above? Let’s hear about them in the comments.

g) Finish the wizard.

Format of Servlet Project

MyServlet (Project Name)
|
|_Web Pages (create html,jsp files here)
|
|-Configuration Files (configure web.xml file)
|
|-Server Resources
|
|-Source Package (create java servlet here)
|
|_Test packages
|
|-Libraries (Add external jar file here)
|
|-Test Libraries

Step 2 : Creating JSP or HTML file
a) Right click on the Web Pages Folder
b) Select New -> HTML option from the pop up window.
c) Type the name of your html page.
d) Finish the wizard.

Eg. select.html

<form action="SelectDetails" method="get">Select the Branch
<select name="branch">
<option value="IT"> B.Tech - IT </option>
<option value="CSE"> B.Tech - CSE </option>
<option value="ECE"> B.Tech - ECE </option>
<option value="MECH"> B.Tech - Mech </option>
</select>
<input type="submit" value="GetDetails" />
</form>

Step 3: MySQL Database : Check Table Name : student
id    name   branch
1     Amar   IT
2     Amit    CSE
3     Antony   MECH
4     Anbu     ECE
103   Sree        MECH
102   Karthick  IT
104   Deepan   ECE
105   Moorthy   CSE

Step 4: Add MySQL Jconnector jar file under “Libraries” foleder
Libraries -> Right Click -> Select Add New Jar File / Folder
My Path : /media/Backup/mysql-connector-java-5.1.6-bin.jar

Step 5: Creating Servlet
a) Right click on the Source Package Folder
b) Select New -> Servlet option from the pop up window.
c) Type the name of your html page.
d) Finish the wizard.

Eg:SelectDetails.java

 
import java.io.IOException;
import java.io.PrintWriter;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.Statement;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
 
public class SelectDetails extends HttpServlet {
 
    protected void processRequest(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        response.setContentType("text/html;charset=UTF-8");
        PrintWriter out = response.getWriter();
        Connection conn = null;
 
        try {
            String branch = request.getParameter("branch");
            String userName = "root";
            String password = "123456";
            String url = "jdbc:mysql://localhost/Check";
            Class.forName("com.mysql.jdbc.Driver").newInstance();
            conn = DriverManager.getConnection(url, userName, password);
            Statement s = conn.createStatement();
            s.executeQuery("SELECT id, name FROM student where branch = '" + branch + "'");
            ResultSet rs = s.getResultSet();
            while (rs.next()) {
                int idVal = rs.getInt("id");
                String nameVal = rs.getString("name");
 
                out.println("id = " + idVal + ", name = " + nameVal +"   ");
 
}
rs.close();
s.close();
 
} catch (Exception e) {
out.println(e.toString());
} finally {
out.close();
if (conn != null) {
                try {
                    conn.close();
                    out.println("Database connection terminated");
                } catch (Exception e) {
                }
            }
 
        }
    }
 
    protected void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        processRequest(request, response);
    }
 
    protected void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        processRequest(request, response);
    }
}

Step 4 : Run the project.
URL => http://localhost:8084/MyServlet/select.html

Output for CSE
id = 2, name = Amit
id = 105, name = Moorthy