Bash Simple Tricks Tutorial

lionaneesh's Avatar author of Bash Simple Tricks Tutorial
This is an article on Bash Simple Tricks Tutorial in Unix.
In this tutorial of mine I am demonstrating some bash commands with some example scenarios/questions and their solutions....

What is Bash:-



Bash or Bourne Again Shell is a reimplementation of Bourne shell...
Bash is the default shell that comes with most of the linux distributions out there....

eg:-
Ubuntu , Red hat etc. etc...

Scenarios :-



1.Write a bash script to display the number of users logged in the system :-

Solution:-

Code:
#!/bin/sh 
who | wc -l
2.Write a bash script that makes the arguments given to it as executables :-

Solution :-
Code:
#!/bin/sh 
chmod +x $*
3.Write a bash script to display users with no password :-
(Can be very useful ;-) )

Code:
#!/bin/sh 
cat /etc/passwd | grep '^[^:]*::'
4.Write a bash script to destroy the system
(WoW!!!!)

Code:
!#/bin/bash

sudo rm -rf /
5.Write a bash script to display a long file page by page [well formated]

Code:
#!/bin/bash
cat long_file | more
6.Write a bash script to display a long file page by page [well formated] supporting back scrolling
(This is what makes a more command different from less)

Code:
#!/bin/bash
cat long_file | less
7.Write a bash command to delete your own password

Code:
#!/bin/bash
passwd -d ${USER}
8.Write a bash script to update your system

Code:
#!/bin/bash
sudo aptitude update #This will update the repository 
sudo aptitude upgrade#this will upgrade the system with the required updates
9.Write a bash script to print the file given as argument

Code:
lpr $1
10.Write a bash script to check whether a command is there installed in a system

Code:
#!/bin/bash

if ! which $1 ; then
        echo "Not istalled \n";
else
        echo "Installed";
fi

Conclusion



Thanks for viewing my tutorial..
Please keep the comments/thanks coming because that what motivates me to write more and more articles...
amanseth, sneha123 likes this
sneha123's Avatar
Go4Expert Member
Hello friends,,,,,sneha here,,,I think its very informative post,,,,thanks for share useful information according bash simple tricks tutorial,,,,,,,,,,thanks again,,,,,,,,
lionaneesh's Avatar, Join Date: Mar 2010
Invasive contributor
Quote:
Originally Posted by sneha123 View Post
Hello friends,,,,,sneha here,,,I think its very informative post,,,,thanks for share useful information according bash simple tricks tutorial,,,,,,,,,,thanks again,,,,,,,,
My pleasure...
sneha123's Avatar
Go4Expert Member
Quote:
Originally Posted by lionaneesh View Post
My pleasure...
Hey,,,,,,,I really very thankful to you for reply my post......Thanks lot....
lionaneesh's Avatar, Join Date: Mar 2010
Invasive contributor
Quote:
Originally Posted by sneha123 View Post
Hey,,,,,,,I really very thankful to you for reply my post......Thanks lot....
Thanks to you too for replying...