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In Linux we can copy files and directories around with the ‘cp’ command. Here we will demonstrate some common examples in which ‘cp’ can be used.

Note: The term ‘directory’ is simply Linux speak for ‘folder’ in Windows.

Copying Files And Directories

The ‘cp’ command works by specifying a source followed by the destination. For example, say we want to copy the /tmp/test file to /root, this would be done as follows.

[root@server ~]# echo "testing" > /tmp/test
[root@server ~]# cat /tmp/test
testing
[root@server ~]# cp /tmp/test /root/
[root@server ~]# cat /root/test
testing

This will copy the source file at /tmp/test to the directory /root/test. As shown when we check the contents of the newly copied /root/test file, they contain the “testing” string which we placed into the original /tmp/test file.

By default if no destination file is specified, the source file name is used, however we can specify the destination file name to be something different if we like, the contents of the file will be the same though.

[root@server ~]# echo "testing2" > /tmp/test2
[root@server ~]# cat /tmp/test2
testing2
[root@server ~]# cp /tmp/test2 /root/newfile
[root@server ~]# cat /root/newfile
testing2

We can also copy a whole directory, simply specify a directory as the source rather than a file name. The destination can either be the directory you wish to copy the source directory into, or it could be a newly named directory.

[root@server ~]# mkdir /tmp/testdir
[root@server ~]# echo "testing3" > /tmp/testdir/testfile3
[root@server ~]# cp -R /tmp/testdir/ /root/
[root@server ~]# cat /root/testdir/testfile3
testing3

For this to work we need the -R flag, which we’ll cover next.

As the ‘cp’ command is for copying, it does not modify the source files or directories, so these will remain safely in place after the copy until you decide to remove them. If you want to move instead of copying, you can instead make use of the ‘mv’ command.

Additional Options

The ‘cp’ command has some useful additional options that we can use to perform specific actions.

Recursive Copy

This option is probably one of the most commonly used and useful available, as it allows us to recursively copy all files and directories within a directory. By default without copying a directory recursively, only the contents within the first level of the directory will be copied over, and not the contents of any sub directories. Using the -r flag will copy everything within recursively.

[root@server ~]# mkdir -p test1/test2/test3
[root@server ~]# touch test1/test1file
[root@server ~]# touch test1/test2/test2file
[root@server ~]# touch test1/test2/test3/test3file
[root@server ~]# cp -r test1/ /tmp/
[root@server ~]# find /tmp/test1/
/tmp/test1/
/tmp/test1/test2
/tmp/test1/test2/test3
/tmp/test1/test2/test3/test3file
/tmp/test1/test2/test2file
/tmp/test1/test1file

In this example, we use mkdir to recursively create the path of directories test1/test2/test3, and we then create a single empty file within each directory with the ‘touch’ command. Next we run the copy with -r set and confirm that all of our files within the sub directories were correctly copied over, and indeed they were.

Force Overwrite Without Confirmation

If you attempt to copy one file over a file that already exists, you will be prompted to confirm that you want to do this by typing ‘y’ or ‘yes’ followed by pressing enter. If you are overwriting hundreds or thousands of files doing this manually would take a very long time. Luckily, there’s a simple way to automatically answer yes to all prompts as shown below.

yes | cp new-file existing-file

The above command will copy the file named ‘new-file’ and overwrite ‘existing-file’ without prompting you for a response as we are piping in yes.

Verbose

With the -v option, we can enable verbose output which will display each file or directory that is copied over as it happens.

[root@server ~]# cp -v test1/test1file /opt/
test1/test1file -> /opt/test1file

Copy Remotely

So far we have covered how you can copy files and directory contents locally to different areas within the same Linux system, now we’ll demonstrate how you can use secure copy with the ‘scp’ command to copy to a remote system over SSH.

In order for this to work, you must have network connectivity from the source system to the destination system. By default SCP uses port 22, however we can set a specific port number with the -P option.

[root@server ~]# echo "testing scp" > /tmp/scp-test
[root@server ~]# scp /tmp/scp-test [email protected]:/root
[email protected]'s password:
scp-test               100%   12     0.0KB/s   00:00

[root@server ~]# ssh [email protected]
[email protected]'s password:
Last login: Sun Jun 12 13:10:32 2016 from 192.168.1.13
[root@client ~]# cat /root/scp-test
testing scp

The example above will copy the /tmp/scp-test file from the local system to the remote host’s /root directory, so long as the user specified has access to this location. We then SSH to the remote server and check the contents of the file have been copied over correctly.

Like ‘cp’, ‘scp’ also supports the -r option for copying recursively.

Summary

As shown we can easily copy files and directories within a Linux bash shell locally on the system with the ‘cp’ command. As a bonus we also covered how to remotely copy files and directories to a remote Linux system with the ‘scp’ command, which runs over the Secure Shell (SSH).