Bash

Bash Script Basic

August 06, 2022 by aAshish

Creating and running a bash script step by step:

  • (Open your text editor)
  • In the editor, add your commands line by line!

echo "number of lines in file:"


wc -l some_data.csv


echo "number of characters in file:"


wc -c some_data.csv
  • Still in the editor, add this line to the very beginning of your bash script:


#!/usr/bin/env bash 
(This line is called the shebang. It tells Ubuntu that your script is in bash.) 

  • Click "10 Quit" in the bottom right corner of the editor and save your file. 
  • Name your file to demo_script.sh (or whatever you prefer)! 
  • Give permission to yourself to run your script. Type this command :
chmod 700 demo_script.sh
  • Run your script by typing this on the command line:
 
./demo_script.sh 

Done!


After running the script, your output will be something like this:

number of lines in file:
672 
number of characters in file:
11424 


You can create various bash scripts (even hundreds of lines long) and even Python or SQL scripts the same way.