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How does Shell find out which command/script I am trying to execute?

This is nothing new but yet I thought why not document it so that its etched into my memory Smile (Ya I know I am selfish Smile with tongue out)

When you run a command or try executing a shell script, the shell first tries to look if your script is found in the Current Directory. To execute a shell script you should be in the same directory where it was created/written.

Now this isn’t possible always – so what to do? There are two ways:

 

Method 1 -

When you are executing the script, give the full path to the script!

Now if you go by the usual file/folder structure in most of the software engineers – you can go crazy with the paths – the depth at which the script is found can drive you insane Surprised smile 

So thankfully we have another way Smile

 

Method 2 -

Add the folder of your script to the PATH variable. What I suggest is create a folder for all your scripts – say myScripts and then add this to your PATH variable.

If you are new to using the PATH variable, I suggest you go through this link on PATH variables

 

So here is how the shell looks for its script to execute: ( I created a small illustration of the same Smile )

image

 

Hope this helps!!!

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