Using filters in Linux

Examples based on filters in Linux.

Links that you may find important :

Sort :

http://linux.about.com/library/cmd/blcmdl1_sort.htm
http://linux.about.com/od/commands/a/Example-Uses-Of-The-Command-Sort.htm
https://www.ibm.com/developerworks/community/blogs/58e72888-6340-46ac-b488-d31aa4058e9c/entry/linux_sort_command_sort_lines_of_text_files9?lang=en

Shell script to rename files based on suffix

Given below is a Shell script to rename files based on suffix.

Links that you may find important :

http://linux.about.com/od/commands/l/blcmdl1_ls.htm
http://en.wikipedia.org/wiki/Ls
http://linux.about.com/library/cmd/blcmdl1_wc.htm
http://www.computerhope.com/unix/uwc.htm
http://en.wikipedia.org/wiki/Wc_%28Unix%29
http://en.wikipedia.org/wiki/Cut_%28Unix%29

Shell scripting using general-purpose utilities - Menu driven program

Given below is a menu driven shell script which will print the following menu and execute the given task to display result on standard output.
MENU
1 Display calendar of current month
2 Display today’s date and time
3 Display usernames those are currently logged in the system
4 Display current directory
5 Display your terminal number
6 Exit

Shell script to display prime numbers

Bash script to display prime numbers.

Links that you may find important :

https://en.wikipedia.org/wiki/Prime_number
http://en.wikipedia.org/wiki/List_of_prime_numbers
http://en.wikipedia.org/wiki/2_%28number%29

Code :

echo 'Enter no'
read x
n=2
while [ $n -le $x ]
do
i=2
count=1

while [ $i -lt $n ]
do
if [ `expr $n % $i` -eq 0 ]
then
count=0
break
fi
i=`expr $i + 1`
done

if [ $count -eq 1 ]
then
echo "$n is Prime"
fi

n=`expr $n + 1`
done

Output :

2 is Prime
3 is Prime
5 is Prime
7 is Prime

Note : Leave a comment if you feel the program is incorrect and/or has errors and/or if the program and its output don't match. Please report about broken links.