Hi friends in this article we shall talk about Linux operating system file system(Directory Structure). File system in Linux is categorized based on the based on nature of files or
directories.

Files are categorized into following types:  


/bin user binaries
/sbin system binaries
/etc configuration files
/dev device files
/proc process files
/var variable files
/tmp temporary files
/usr user programs
/home home directory
/boot boot loader files
/lib library files
/opt optional-add-on apps
/mnt mount directory
/media removable devices

/sv
service data

In Linux operating system  "/"  represents root directory which means it is a parent directory for Linux file system.

/bin: This directory contains binary executable s,  Common Linux commands you need
        to use in single-user modes are located under this directory.
Ex :   



/sbin:  This directory contains binary executable s, But  the linux commands located  
           under this directory are used typically by system administrator for system 
           maintenance purpose.
Ex :   


/etc:  This directory contains configuration files required by all programs ,This also   
         contains startup and shutdown shell scripts used to start/stop individual programs.
/Ex : 

 
/dev:  This directory contains device files and also contains files for handling removable 
          devices.
/Ex :  

 
   /proc:  This directory Contains information about system.This is a pseudo filesystem 
             process contains information about running process.
   /Ex :    

     
                                                                                      

/var: Variable means it contains variable length records. which means Content of the files          that are expected to grow can be found under this directory.
/Ex :  

   
                                                                                                                      

/tmp: Directory that contains temporary files created by system and users.Files under 
         this are get deleted when system rebooted.     
                 
/user: Contains binaries, libraries, documentation, and source-code for second level
          programs. It has also sub directories like bellow image.


/home: Home directories for all users to store their personal files.

/boot:  Contains boot loader related files like bellow image.


/lib    :   Contains library files that supports the binaries located under /bin and /sbin  

                                                                                                                                
/opt  : opt stands for optional,Contains add-on applications from individual vendors.

/mnt : Temporary mount directory where sysadmins can mount filesystems.

/media :  Temporary mount directory for removable devices.

/srv: srv stands for service Contains server specific services related data.

                                                             

                                                                                                                                                                                                                                        

                                                                                                                                                                                                                                                                                                                                                                                                                                                      
 







This is a simple c language project using structures  concept.Basic bank operations 
are implemented in this simple project there will be a menu driven option for the
user based on the user selection operations will be done.

 


/*Simple c project using structures*/
#include<stdio.h>
#include<conio.h>
void creation();
void deposit();
void withdraw();
void bal();
int a=0,i = 101;
struct bank
{
int no;
char name[20];
float bal;
float dep;
}s[20];
void main()
{
int ch;
while(1)
{
clrscr();
printf("\n*********************");
printf("\n BANKING ");
printf("\n*********************");
printf("\n1-Creation");
printf("\n2-Deposit");
printf("\n3-Withdraw");
printf("\n4-Balance Enquiry");
printf("\n5-Exit");
printf("\nEnter your choice");
scanf("%d",&ch);
switch(ch)
{
case 1: creation();
break;
case 2: deposit();
break;
case 3: withdraw();
break;
case 4: bal();
break;
case 5: exit(0);
defalut: printf("Enter 1-5 only");
getch();
}
}
}
void creation()
{
printf("\n*************************************");
printf("\n ACCOUNT CREATION ");
printf("\n*************************************");
printf("\nYour Account Number is :%d",i);
s[a].no = i;
printf("\nEnter your Name:");
scanf("%s",s[a].name);
printf("\nYour Deposit is Minimum Rs.500");
s[a].dep=500;
a++;
i++;
getch();
}
void deposit()
{
int no,b=0,m=0;
float aa;
printf("\n*************************************");
printf("\n DEPOSIT ");
printf("\n*************************************");
printf("\nEnter your Account Number");
scanf("%d",&no);
for(b=0;b<i;b++)
{
if(s[b].no == no)
m = b;
}
if(s[m].no == no)
{
printf("\n Account Number : %d",s[m].no);
printf("\n Name : %s",s[m].name);
printf("\n Deposit : %f",s[m].dep);
printf("\n How Much Deposited Now:");
scanf("%f",&aa);
s[m].dep+=aa;
printf("\nDeposit Amount is :%f",s[m].dep);
getch();
}
else
{
printf("\nACCOUNT NUMBER IS INVALID");
getch();
}
}
void withdraw()
{
int no,b=0,m=0;
float aa;
printf("\n*************************************");
printf("\n WITHDRAW ");
printf("\n*************************************");
printf("\nEnter your Account Number");
scanf("%d",&no);
for(b=0;b<i;b++)
{
if(s[b].no == no)
m = b;
}
if(s[m].no == no)
{
printf("\n Account Number : %d",s[m].no);
printf("\n Name : %s",s[m].name);
printf("\n Deposit : %f",s[m].dep);
printf("\n How Much Withdraw Now:");
scanf("%f",&aa);
if(s[m].dep<aa+500)
{
printf("\nCANNOT WITHDRAW YOUR ACCOUNT HAS MINIMUM BALANCE");
getch();
}
else
{
s[m].dep-=aa;
printf("\nThe Balance Amount is:%f",s[m].dep);
}
}
else
{
printf("INVALID");
getch();
}
getch();
}
void bal()
{ int no,b=0,m=0;
float aa;
printf("\n*************************************");
printf("\n BALANCE ENQUIRY ");
printf("\n*************************************");
printf("\nEnter your Account Number");
scanf("%d",&no);
for(b=0;b<i;b++)
{
if(s[b].no == no)
m = b;
}
if(s[m].no==no)
{
printf("\n Account Number : %d",s[m].no);
printf("\n Name : %s",s[m].name);
printf("\n Deposit : %f",s[m].dep);
getch();
}
else
{
printf("INVALID");
getch();
}
}







Hi Friends Learning core java is a first step in to java programming we are confused what topics are come under core java section and core java is very essential for building logic's  for every high end applications,so i listed all topics in table format.  



Basic Java

OOPS Concepts

Advanced Topics of java
 Learn introduction Objects and Class String handling
Know features of java Polymorphism Exception handling
Setting class path Constructor Multithreading
Know About Data Types This reference Synchronization
Write basic program Garbage collection Enumeration
Variable rules Java modifiers Auto Boxing and Un Boxing
Operators in java Inheritance Java I/O stream

Aggregation Serialization

Command line arguments Generics

Packages Collection framework

Abstraction Java Networking

interfaces Applets

Nested class AWT and Swings
Setting Classpath for Java








Java is freely available on Oracle's Website. Download the latest version of JDK (Java Development Kit) on your operating system. Install JDK on your machine. Once you have installed Java on your machine you would need to set environment variable to point to correct installation directory. 

PROCEDURE:

   Assuming that you have installed Java in C:\ Program files/ Java / JDK directory

Step 1:Right click on my computer and select properties.
















Step 2:Go to the Advance System Settings tab.

 











Step 3:Click on Environment Variables button.

 























Step 4: Now alter the path variable so that it also contains the path to JDK installed
           directory.

 





















 Step 5: Select path and click on edit and past class path.Click on ok button.
 Step 6: Now go to command prompt and type java and javac, If you successfully
            make it you will see commands acknowledge.
 Step 7: That's it your done!
Professional syntax highlighter for blog posts

Syntax highlighting is a special  feature which highlights source code in blogger posts. It displays text, especially source code  in different colors and fonts according to the category of terms. This feature facilitates writing in a structured language such as a programming language or a markup language  as both structures and syntax errors are visually distinct. Highlighting does not affect the meaning of the text itself; it is intended only for human readers.(Wikipedia).

Procedure for adding syntax highlighter:

   1. First of All go to Blogger dashboard.
    2. Then Click On Template Tab
    3. Press Control+F search for </head>
    4. Paste the bellow code just before  </head>


<link href='http://alexgorbatchev.com/pub/sh/current/styles/shCore.css' rel='stylesheet' type='text/css'/>
<link href='http://alexgorbatchev.com/pub/sh/current/styles/shThemeEclipse.css' rel='stylesheet' type='text/css'/>
<script src='http://alexgorbatchev.com/pub/sh/current/scripts/shCore.js' type='text/javascript'/>
<script src='http://alexgorbatchev.com/pub/sh/current/scripts/shBrushCSharp.js' type='text/javascript'/>
<script src='http://alexgorbatchev.com/pub/sh/current/scripts/shBrushCpp.js' type='text/javascript'/>
<script src='http://alexgorbatchev.com/pub/sh/current/scripts/shBrushCss.js' type='text/javascript'/>
<script src='http://alexgorbatchev.com/pub/sh/current/scripts/shBrushJScript.js' type='text/javascript'/>
<script src='http://alexgorbatchev.com/pub/sh/current/scripts/shBrushJava.js' type='text/javascript'/>
<script src='http://alexgorbatchev.com/pub/sh/current/scripts/shBrushPhp.js' type='text/javascript'/>
<script src='http://alexgorbatchev.com/pub/sh/current/scripts/shBrushPlain.js' type='text/javascript'/>
<script src='http://alexgorbatchev.com/pub/sh/current/scripts/shBrushSql.js' type='text/javascript'/>
<script src='http://alexgorbatchev.com/pub/sh/current/scripts/shBrushXml.js' type='text/javascript'/>
<script language='javascript' type='text/javascript'>
SyntaxHighlighter.config.bloggerMode = true;
SyntaxHighlighter.all();
</script>



5. Save the template.
6. First you have convert source code into html escaped code using follow link htmlescape
7. While writing your blog post enclose your html escaped code  between following tags

C       <pre class="brush:c";> sourcecode </pre>
java   <pre class="brush:java";> sourcecode </pre>
php    <pre class="brush:php";> sourcecode </pre>
html   <pre class="brush:html";> sourcecode </pre>
Sql     <pre class="brush:sql";> sourcecode </pre>

6. That's it your done.