Bash is a scripting language used to interact with your terminal. There are few useful commands to remember in order to be able to navigate, install or remove files. This article brings a summary of the most useful ones:
Moving directory and files location
These useful commands are useful to navigate through your files, create folders, move a file or delete it.
> cd some/path/you/want/to/go : change directory
> cd .. : moving to the parent of the current directory
> ls : list of content in current directory
> pwd : path of the current directory
> mkdir : create a directory
> cp : copy a file
> mv : move a file
> rm : delete a file
Conditional execution
You don’t always want to execute a single command, but you might want to execute two in a row, or execute one if the first failed.
> cd some/path/you/want/to/go && ls : execute first statement then second statement
> rm filename || echo "Delete failed" : delete the file, but if there is an error, display "Delete failed"
Execute a Python file
Often, you will need to execute Python files (.py files). In this case, all you need to do run python and the name of the file:
> pyton myfile.py
Defining a variable
Defining a variable is useful when you want to define a path that is re-used often. For example, say you placed a program you downloaded in a specific folder, you could define:
> path="Users/myname/myprogram"
Then, if you want to access this path as a variable, simply execute:
> echo $path
Reading a file
Reading a file through the terminal is useful when your file is in a format you can’t open natively or relatively large. You can either use cat:
cat myfile.txt
Or do it iteratively:
< myfile.txt | while read line; do
echo $line
done
Conditions
Finally, there are cases where you need to execute a command under certain conditions. This is handled by the if-statement.
if mycondition; then
echo "Statement A"
elif myothercondition; then
echo "Statement A"
fi
This is a summary of the most common use cases of bash scripting for your terminal. If you would like to dig deeper, take a look at the extensive list of the useful bash commands available here.
Don’t hesitate to leave a comment and tell me what commands you use the most and why.