Why ~/USERNAME/bin/some_custom_command does not work as expected?

Question

I read "Linux Bible 10th Edition", chapter 3: Using the shell, at 70 page. There is Tip section:

If you want to add your own commands or shell scripts, place them in the bin directory in your home directory (such as /home/cn/bin for the user named cn). This directory is automatically added to your path in some Linux systems, although you may need to create that directory or add it to your PATH on other Linux systems. So, as long as you add the command to your bin with execute permission, you can begin using it by simply typing the command name at your shell prompt. To make commands available to all users, add them to /usr/local/bin

I'm running Fedora Linux 35 Workstation Edition and trying to create my custom command. I've created ~/bin/kek.sh

#! /usr/bin/bash
echo "Kek"

and go to the command line, enter kek in my home directory. I got bash: kek: command not found.... After that I went to my ~/.bashrc and added following lines at the end of file

PATH=$PATH:~/home/bin/kek; export PATH;

Then returned to ~ directory, entered kek and got the same bash: kek: command not found.... I've changed .bashrc PATH line to PATH=$PATH:~/home/bin; export PATH;, reload terminal session and always getting the same result.

Please, explain, why it didn't work for me? How can I create my own command and make it accessible just by it's name? Thank you.

Answer 1

The PATH variable indicates to your shell where executables may exist. So if you are placing your script kek.sh under ~/bin, then you would want to add ~/bin to PATH. However it appears that you have added ~/home/bin/kek to your PATH instead.

Another problem is that the script is named kek.sh, however the command you are trying to execute is kek. Either you need to change the name of kek.sh to kek or you need to be running kek.sh as your command.

Putting #!/usr/bin/bash at the top of your script (known as a shebang) indicates to the system what interpreter should be used on the script. Naming it with a .sh at the end does not affect how the shell executes the script as far as I know, so simply naming it kek would not change how it is executed so long as the proper interpreter is in place after #!