Create, Copy, Rename, and Remove Unix Files and Directories

This document lists commands for creating, copying, renaming, and deleting Unix files and directories. It assumes that you are using Unix on the ITS login service (login.itd.umich.edu). The instructions here apply to many other Unix machines; however, if you do not use ITS to log in to the service, you may notice different behavior.

What Are Unix Files and Directories?

A file is a "container" for data. Unix makes no distinction among file types—a file may contain the text of a document, data for a program or the program itself.

Directories provide a way to organize files, allowing you to group related files together. Directories may contain files and/or other directories. Directories are analogous to Macintosh and Windows folders.

Naming Unix Files and Directories

Each file and directory has a name. Within a directory, each item (that is, each file or directory) must have a unique name, but items with the same name may exist in more than one directory. A directory may have the same name as one of the items it contains.

File and directory names may be up to 256 characters long. Names may use almost any character (except a space). You can divide a multi-word file name using either an underscore or a period (for example,

chapter_one

or

chapter.two

).

Some characters have special meanings to Unix. It is best to avoid using these characters in file names:

Unix is case-sensitive. Each of these is a unique file:

myfile, Myfile, myFile,

and

MYFILE

.

Creating a File

Many people create files using a text editor, but you can use the command

cat

to create files without using/learning to use a text editor. To create a practice file (called

firstfile

) and enter one line of text in it, type the following at the

%

prompt:

Terminate file entry by typing

Control-d

on a line by itself. (Hold down the Control key and type d.) On your screen, you will see:

To examine the contents of a file you have just created, enter this at the

%

prompt:

Copying a File

To make a duplicate copy of a file, use the command

cp

. For example, to create an exact copy of the file called

firstfile,

you would type:

This results in two files with different names, each containing the same information. The

cp

command works by overwriting information. If you create a different file called

thirdfile

and then type the following command:

you will find that the original contents of

firstfile

are gone, replaced by the contents of

thirdfile

.

Renaming a File

Unix does not have a command specifically for renaming files. Instead, the

mv

command is used both to change the name of a file and to move a file into a different directory.

To change the name of a file, use the following command format (where

thirdfile

and

file3

are sample file names):

This command results in the complete removal of

thirdfile

, but a new file called

file3

contains the previous contents of

thirdfile.

Like

cp,

the

mv

command also overwrites existing files. For example, if you have two files,

fourthfile

and

secondfile,

and you type the command

mv

will remove the original contents of

secondfile

and replace them with the contents of

fourthfile

. As a result,

fourthfile

is renamed

secondfile

, but in the process

secondfile

is deleted.

Removing a File

Use the

rm

command to remove a file. For example,

deletes

file3

and its contents. You may remove more than one file at a time by specifying a list of files to be deleted. For example,

You will be prompted to confirm whether you really want to remove the files:

Type

y

or

yes

to remove a file; type

n

or

no

to leave it intact.

Creating a Directory

creates a directory called

project1,

where you can store files related to a particular project. The directory that you create will be a subdirectory within your current directory. For details on how to navigate directories and display the files and directories they contain, see

List Contents and Navigate Unix Directories.

Moving and Copying Files Into a Directory

The

mv

and

cp

commands can be used to put files into a directory. Assume that you want to place some files from your current directory into a newly created directory called

project1.

The command

will move the file

bibliography

into the directory

project1

. The command

will place a copy of the file

chapter1

in the directory

project1

, but leave

chapter1

@a_shell_ios Vim user discovering a-shell (and thrilled), but with limited Unix skills… Please consider creating ne… https://t.co/9XWonLUSAs

— tjg Thu Nov 05 09:09:00 +0000 2020

intact in the current directory. There will now be two copies of

chapter1

, one in the current directory and one in

project1

.

Renaming a Directory

You can also use the

mv

command to rename and move directories. When you type the command

the directory called

project1

will be given the new name

project2

as long as a directory called

project2

did not previously exist. If directory

project2

already existed before the mv command was issued,

would move the directory

project1

and its files into the directory

project2.

Copying a Directory

You can use the

cp

command to create a duplicate copy of a directory and its contents. To copy directory

project1

to directory

proj1copy,

for example, you would type

If directory

proj1copy

already exists, this command will put a duplicate copy of

directory project1

into directory

proj1copy\

.

Removing a Directory

Use the command

rmdir

to remove an empty directory. Multiple empty directories may be removed by listing them after the command:

If you try to remove a directory that is not empty, you will see

rmdir: testdir3: Directory not empty

If you are sure that you want to remove the directory and all the files it contains, use the command

Summary of Commands

Working With Files

mv file1 file2

Renames

file1

to

file2

(if

file2

existed previously, overwrites original contents of

file2

).

cp file1 file2

Copies

file1

as

file2

(if

file2

existed previously, overwrites original contents of

file2

).

rm file3 file4

Removes

file3

and

file4,

requesting confirmation for each removal.

Working With Directories

mkdir dir1

Creates a new directory called

dir1.

mv dir1 dir2

If

dir2

does not exist, renames

dir1

to

dir2.

If

dir2

exists, moves

dir1

inside

dir2.

cp -r dir1 dir2

If

dir2

does not exist, copies

dir1

as

dir2.

If

dir2

does exist, copies

dir1

inside

dir2.

rmdir dir1

Removes

dir1,

if

dir1

contains no files.

rm -r dir1

Removes

dir1

and any files it contains. Use with caution.

Working With Files and Directories

cp file1 dir1

Copies file

file1

into existing directory

dir1

.

mv file2 dir2

Moves file

file2

into existing directory

dir2

.