If you have ever owned a computer before, then you know how important it is to be able to copy and move files around. That's why I dedicated an entire chapter to talk just about that: copying, moving, and deleting files.
Copying one file
Sometimes you need to copy a single file. Luckily this is a simple operation on the command line. I have a file named cats.txt in my home directory:
elliot@ubuntu-linux:~$ cat cats.txt
I love cars!
I love cats!
I love penguins!
elliot@ubuntu-linux:~$
I can use the cp command to make a copy of cats.txt named copycats.txt as follows:
elliot@ubuntu-linux:~$ cp cats.txt copycats.txt
elliot@ubuntu-linux:~$ cat copycats.txt
I love cars!
I love cats!
I love penguins!
elliot@ubuntu-linux:~$
As you can see, the copied file copycats.txt has the same content as the original file cats.txt.
I can also copy the file cats.txt to another directory. For example, I can copy the file cats.txt to /tmp by running the cp cats.txt /tmp command:
elliot@ubuntu-linux:~$ cp cats.txt /tmp
elliot@ubuntu-linux:~$ cd /tmp
elliot@ubuntu-linux:/tmp$ ls
cats.txt
elliot@ubuntu-linux:/tmp$
Notice that the copied file has the same name as the original file. I can also make another copy in /tmp with a different name:
elliot@ubuntu-linux:~$ cp cats.txt /tmp/cats2.txt
elliot@ubuntu-linux:~$ cd /tmp
elliot@ubuntu-linux:/tmp$ ls
cats2.txt cats.txt
elliot@ubuntu-linux:/tmp$
Copying multiple files
You may also want to copy multiple files at once. To demonstrate, let's begin by creating three files apple.txt, banana.txt, and carrot.txt in Elliot's home directory:
elliot@ubuntu-linux:~$ touch apple.txt banana.txt carrot.txt
elliot@ubuntu-linux:~$ ls
apple.txt carrot.txt copycats.txt dir1
banana.txt cats.txt Desktop
elliot@ubuntu-linux:~$
To copy the three newly created files to /tmp, you can run the cp apple.txt ba- nana.txt carrot.txt /tmp command:
elliot@ubuntu-linux:~$ cp apple.txt banana.txt carrot.txt /tmp
elliot@ubuntu-linux:~$ cd /tmp
elliot@ubuntu-linux:/tmp$ ls
apple.txt banana.txt carrot.txt cats2.txt cats.txt
elliot@ubuntu-linux:/tmp$
Child’s play! In general, the cp command follows the syntax:
cp source_file(s) destination
Copying one directory
You may also want to copy an entire directory; that's also easily accomplished. To demonstrate, create a directory named cities in your home directory, and inside cities, create three files paris, tokyo, and london as follows:
elliot@ubuntu-linux:~$ mkdir cities
elliot@ubuntu-linux:~$ cd cities/
elliot@ubuntu-linux:~/cities$ touch paris tokyo london
elliot@ubuntu-linux:~/cities$ ls
london paris tokyo
Now if you want to copy the cities directory to /tmp, you have to pass the recursive -r option to the cp command as follows:
elliot@ubuntu-linux:~/cities$ cd ..
elliot@ubuntu-linux:~$ cp -r cities /tmp
You will get an error message if you omitted the -r option:
elliot@ubuntu-linux:~$ cp cities /tmp
cp: -r not specified; omitting directory 'cities'
You can verify that the cities directory is copied to /tmp by listing the files in /tmp:
elliot@ubuntu-linux:~$ cd /tmp
elliot@ubuntu-linux:/tmp$ ls
apple.txt banana.txt carrot.txt cats2.txt cats.txt cities
elliot@ubuntu-linux:/tmp$ ls cities
london paris tokyo
Copying multiple directories
You can also copy multiple directories the same way you copy multiple files; the only difference is that you have to pass the recursive -r option to the cp command.
To demonstrate, create the three directories d1, d2, and d3 in Elliot's home directory:
elliot@ubuntu-linux:~$ mkdir d1 d2 d3
Now you can copy all three directories to /tmp by running the cp -r d1 d2 d3 /tmp command:
elliot@ubuntu-linux:~$ cp -r d1 d2 d3 /tmp
elliot@ubuntu-linux:~$ cd /tmp
elliot@ubuntu-linux:/tmp$ ls
apple.txt banana.txt carrot.txt cats2.txt cats.txt cities d1 d2 d3
Moving one file
Sometimes, you may want to move a file (or a directory) to a different location instead of copying and wasting disk space.
To do this, you can use the mv command. For example, you can move the file copycats.txt from Elliot's home directory to /tmp by running the mv copycats.txt /tmp command:
elliot@ubuntu-linux:~$ mv copycats.txt /tmp
elliot@ubuntu-linux:~$ ls
apple.txt carrot.txt cities d2 Desktop Downloads
banana.txt cats.txt d1 d3 dir1 Pictures
elliot@ubuntu-linux:~$ cd /tmp
elliot@ubuntu-linux:/tmp$ ls
apple.txt carrot.txt cats.txt copycats.txt d2
banana.txt cats2.txt cities d1 d3
Notice that copycats.txt is now gone from Elliot's home directory as it relocated to /tmp.
Moving multiple files
You can also move multiple files the same way you can copy multiple files. For example, you can move the three files apple.txt, banana.txt, and carrot.txt from /tmp to /home/elliot/d1 as follows:
elliot@ubuntu-linux:/tmp$ mv apple.txt banana.txt carrot.txt /home/elliot/d1
elliot@ubuntu-linux:/tmp$ ls
cats2.txt cats.txt cities copycats.txt d1 d2 d3
elliot@ubuntu-linux:/tmp$ cd /home/elliot/d1
elliot@ubuntu-linux:~/d1$ ls
apple.txt banana.txt carrot.txt
elliot@ubuntu-linux:~/d1$
As you can see, the three files apple.txt, banana.txt, and carrot.txt are no longer located in /tmp as they all moved to /home/elliot/d1. In general, the mv command follows the syntax:
mv source_file(s) destination
Moving one directory
You can also use the mv command to move directories. For example, if you want to move the directory d3 and put it inside d2, then you can run the mv d3 d2 command:
elliot@ubuntu-linux:~$ mv d3 d2
elliot@ubuntu-linux:~$ cd d2
elliot@ubuntu-linux:~/d2$ ls
d3
elliot@ubuntu-linux:~/d2$
Notice that you don't need to use the recursive -r option to move a directory.
Moving multiple directories
You can also move multiple directories at once. To demonstrate, create a directory named big in Elliot's home directory:
elliot@ubuntu-linux:~$ mkdir big
Now you can move the three directories d1, d2, and cities to the big directory as follows:
elliot@ubuntu-linux:~$ mv d1 d2 cities big
elliot@ubuntu-linux:~$ ls big
cities d1 d2
elliot@ubuntu-linux:~$
Renaming files
You can also use the mv command to rename files. For example, if you want to rename the file cats.txt to dogs.txt, you can run the mv cats.txt dogs.txt command:
elliot@ubuntu-linux:~$ mv cats.txt dogs.txt
elliot@ubuntu-linux:~$ cat dogs.txt
I love cars!
I love cats!
I love penguins!
elliot@ubuntu-linux:~$
If you want to rename the directory big to small, you can run the mv big small command:
elliot@ubuntu-linux:~$ mv big small
elliot@ubuntu-linux:~$ ls small
cities d1 d2
elliot@ubuntu-linux:~$
In summary, here is how the mv command works:
- If the destination directory exists, the mv command will move the source file(s) to the destination directory.
- If the destination directory doesn’t exist, the mv command will rename the source file.
Keep in mind that you can only rename one file (or one directory) at a time.
Hiding files
You can hide any file by renaming it to a name that starts with a dot.
Let's try it; you can hide the file dogs.txt by renaming it to .dogs.txt as follows:
elliot@ubuntu-linux:~$ ls
apple.txt banana.txt carrot.txt dogs.txt Desktop dir1 small
elliot@ubuntu-linux:~$ mv dogs.txt .dogs.txt
elliot@ubuntu-linux:~$ ls
apple.txt banana.txt carrot.txt Desktop dir1 small
elliot@ubuntu-linux:~$
As you can see, the file dogs.txt is now hidden as it got renamed to .dogs.txt. You can unhide .dogs.txt by renaming it and removing the leading dot from the filename:
elliot@ubuntu-linux:~$ mv .dogs.txt dogs.txt
elliot@ubuntu-linux:~$ ls
apple.txt banana.txt carrot.txt dogs.txt Desktop dir1 small
elliot@ubuntu-linux:~$
Yes, Sir! You can also hide and unhide directories in the same manner. I will leave that for you to do as an exercise.
Removing files
You can use the rm command to remove (delete) files. For example, if you want to remove the file dogs.txt, you can run the rm dogs.txt command:
elliot@ubuntu-linux:~$ ls
apple.txt banana.txt carrot.txt dogs.txt Desktop dir1 small
elliot@ubuntu-linux:~$ rm dogs.txt
elliot@ubuntu-linux:~$ ls
apple.txt banana.txt carrot.txt Desktop dir1 small
You can also remove multiple files at once. For example, you can remove the three files apple.txt, banana.txt, and carrot.txt by running the rm apple.txt banana.txt carrot.txt command:
elliot@ubuntu-linux:~$ rm apple.txt banana.txt carrot.txt
elliot@ubuntu-linux:~$ ls
Desktop dir1 small
elliot@ubuntu-linux:~$
Removing directories
You can pass the recursive -r option to the rm command to remove directories. To demonstrate, let’s first create a directory named garbage in Elliot's home directory:
elliot@ubuntu-linux:~$ mkdir garbage
elliot@ubuntu-linux:~$ ls
Desktop dir1 garbage small
Now let's try to remove the garbage directory:
elliot@ubuntu-linux:~$ rm garbage
rm: cannot remove 'garbage': Is a directory
elliot@ubuntu-linux:~$
Shoot! I got an error because I didn't pass the recursive -r option. I will pass the recursive option this time:
elliot@ubuntu-linux:~$ rm -r garbage
elliot@ubuntu-linux:~$ ls
Desktop dir1 small
Cool! We got rid of the garbage directory.
You can also use the rmdir command to remove only empty directories. To demonstrate, let’s create a new directory named garbage2 and inside it, create a file named old:
elliot@ubuntu-linux:~$ mkdir garbage2
elliot@ubuntu-linux:~$ cd garbage2
elliot@ubuntu-linux:~/garbage2$ touch old
Now let's go back to Elliot's home directory and attempt to remove garbage2 with the rmdir command:
elliot@ubuntu-linux:~/garbage2$ cd ..
elliot@ubuntu-linux:~$ rmdir garbage2
rmdir: failed to remove 'garbage2': Directory not empty
As you can see, it wouldn’t allow you to remove a nonempty directory. Therefore, let's delete the file old that’s inside garbage2 and then reattempt to remove garbage2:
elliot@ubuntu-linux:~$ rm garbage2/old
elliot@ubuntu-linux:~$ rmdir garbage2
elliot@ubuntu-linux:~$ ls
Desktop dir1 small
elliot@ubuntu-linux:~$
Boom! The garbage2 directory is gone forever. One thing to remember here is that the rm -r command will remove any directory (both empty and nonempty). On the other hand, the rmdir command will only delete empty directories.
For the final example in this chapter, let's create a directory named garbage3, then create two files a1.txt and a2.txt inside it:
elliot@ubuntu-linux:~$ mkdir garbage3
elliot@ubuntu-linux:~$ cd garbage3/
elliot@ubuntu-linux:~/garbage3$ touch a1.txt a2.txt
elliot@ubuntu-linux:~/garbage3$ ls
a1.txt a2.txt
Now let's get back to Elliot's home directory and attempt to remove garbage3:
elliot@ubuntu-linux:~/garbage3$ cd ..
elliot@ubuntu-linux:~$ rmdir garbage3
rmdir: failed to remove 'garbage3': Directory not empty
elliot@ubuntu-linux:~$ rm -r garbage3
elliot@ubuntu-linux:~$ ls
Desktop dir1 Downloads Pictures small
elliot@ubuntu-linux:~$
As you can see, the rmdir command has failed to remove the nonempty directory garbage3, while the rm -r command has successfully removed it.
Nothing makes information stick in your head like a good knowledge-check exercise.
Knowledge check
For the following exercises, open up your Terminal and try to solve the following tasks:
- Create three files hacker1, hacker2, and hacker3 in your home directory.
- Create three directories Linux, Windows, and Mac in your home directory.
- Create a file named cool inside the Linux directory you created in task 2.
- Create a file named boring inside the Windows directory you created in task 2.
- Create a file named expensive in the Mac directory you created in task 2.
- Copy the two files hacker1 and hacker2 to the /tmp directory.
- Copy the two directories Windows and Mac to the /tmp directory.
- Move the file hacker3 to the /tmp directory.
- Move the directory Linux to the /tmp directory.
- Remove the file expensive from the Mac directory (in your home directory).
- Remove the directory Mac from your home directory.
- Remove the directory Windows from your home directory.
- Remove the file hacker2 from your home directory.
- Rename the file hacker1 to hacker01.
True or false
- The cp command can copy directories without using the recursive option -r.
- You have to use the recursive option -r when moving directories.
- You can use the mv command to rename files or directories.
- You can remove a non-empty directory with the rmdir command.
- You can remove a non-empty directory with the rm -r command.