Steps to write Shell Script?
By following the below steps you can write shell script:-
1) You can use any editor like vi or mcedit to write shell script.
2) Once you have written shell script set execute permission for your script which are as follows
syntax:
chmod permission your-script-name
Examples:
$ chmod +x your-script-name
$ chmod 755 your-script-name
Note: This will set read write execute(7) permission for owner, for group and other permission is read and execute only(5).
3) Now execute your script as
syntax:
bash your-script-name
sh your-script-name
./your-script-name
Examples:
$ bash bar
$ sh bar
$ ./bar
NOTE In the last syntax ./ means current directory, But only . (dot) means execute given command file in current shell without starting the new copy of shell, The syntax for . (dot) command is as follows
Syntax:
. command-name
Example:
$ . foo
Now you are ready to write first shell script that will print “Knowledge is Power” on screen. See the common vi command list , if you are new to vi.
$ vi first
#
# My first shell script
#
clear
echo “Knowledge is Power”
After saving the above script, you can run the script as follows:
$ ./first
This will not run script since we have not set execute permission for our script first; to do this type command
$ chmod 755 first
$ ./first
First screen will be clear, then Knowledge is Power is printed on screen.