I need to create a script that uses a dynamic filename for the cat command

Question

I'm working in Linux. When I use the terminal, I can open a file like this:

cat filename > /dev/null

I need to create a script that performs this task above. So I created a script named scriptname using nano & chmod +x, and it contains the line of code above.

When I call the script it will specifically look for 'filename,' but what I need is to enter a dynamic filename like scriptname userDefinedFilename. So the bolded part of the code below needs to be dynamically replaceable with user input.

cat filename > /dev/null

Is there a specific name for this kind of scripting within linux? Knowing the name would really help me find these answers through google in the feature.

Answer 1

If it is just a parameter (the filename) you can read it from command line with $1 How do I parse command line arguments in Bash? You can also read inside your script with read: http://tldp.org/LDP/Bash-Beginners-Guide/html/sect_08_02.html The name is bash scripting or bash programming: http://tldp.org/HOWTO/Bash-Prog-Intro-HOWTO.html If you use a different shell (different from bash) you'll have to learn the peculiarities for this shell.