Additive color mixing begins with black and ends with white; as more color is added, the result is lighter and tends to white. The RGB colors are light primaries and colors are created with light. Percentages of red, green, & blue light are used to generate color on a computer screen.
In shell scripting we often need to check if file or directory exists and take appropriate action. This post show you how to check it and how this check use in your script. For checking we will use file test operators -f for file and -d for directory, which return TRUE if file or directory exists. And here is output of the script.
Shell scripting can be defined as a group of commands executed in sequence. Let's start by describing the steps needed to write and execute a shell script: Step 1: Open the file using an editor (e.g., vi or pico.). Step 2: All shell scripts should begin with #!/bin/bash or whatever other shell you prefer.tep 3: Write the code that you want to develop. Our first shell script will be the usual Hello World routine, which we'll place in a file called 'Firstshellscript.sh'. Step 4:The next step is to make the script executable by using the chmod command.