For this Linux/Unix bash shell tutorial, we have an extra special field trip planned in the “Petting Zoo” directory. Seatbelts everyone!
cd "Petting Zoo"
Lets take a look around. Use the “ls” command to list the directory contents.
Llamas, turkeys, and bison, oh my! I’d like to know a bit more about these files. The “-l” option shows us the file’s permissions, group owner, file size, and date last modified. Radical!
Oh no! That poor llama hasn’t been modified in years! How sad, it must be lonely. Lets “touch” it.
Touching a file updates the access and modification time of the file, so if we list the petting zoo directory contents again…
We see the llama has been “touched” recently. Doesn’t that just make you feel all warm inside?
Lets touch everything!
Ouch! That hedgehog was unpleasant, but you know what would be amazing? A unicorn.
It may not look like anything happened, but you have to believe!
Check it out! The touch command created a new file when we requested a file that didn’t exist. Magical!
This unicorn seems lonely and empty, I think she needs a friend. Lets make one with the cp command.
cp unicorn unicorn_copy
They should get along nicely, seeing as they are identical twins.
Not all files live out in the open, we can use the “-a” option with “ls” to show any hidden files.
Oh em gee! It’s a “.chupacabra”. Wait, what is a chupacabra? The “file” command will shed some light on this.
It’s worse than I could possibly have imagined. The .chupacabra is a Windows executable, and it’s upsetting the free and open-range files! It’s time for some good old-fashioned human intervention.
The .chupacabra is gone.
But what’s this hidden “.den”?
It’s a directory! Lets see what’s inside.
ls -a .den
Holy blood-sucking cryptids! More “.chupacabras”. We need to recursively remove that “.den” directory, stat!
rm -r .den ls -a
Peace has been restored to the “Petting Zoo” directory. Lets head home.
Lets review what we learned on our field trip:
- ls lists the contents of a directory.
- touch updates the date accessed and date modified times of a file.
- If touch is given a non-existent file, it will create one for you.
- the file command describes the file type.
- cp copies a file.
- rm removes a file.
- rm -r removes a directory and all of the files and directories inside of it.
Featured image credit: Sam Howzit