commands cp - mv - mkdir - rm - ln

Linux offers a powerful and flexible way to manage files and directories using the command line interface (CLI). While graphical file managers are convenient for basic tasks, CLI commands allow for complex file operations with precision.
This article explores five essential Linux commands for file manipulation, as well as wildcards that simplify file selection.
Essential File and Directory Commands The following commands enable efficient management of files and directories: cp – Copy files and directories mv – Move or rename files and directories mkdir – Create new directories rm – Remove files and directories ln – Create hard and symbolic links
Using the command line interface provides capabilities that go beyond basic file operations. For instance, copying files selectively based on their modification time can be accomplished with:

This command ensures that only new or modified .html files are copied, avoiding unnecessary duplication.
Understanding Wildcards in Linux Wildcards allow users to select multiple filenames based on patterns, making file management more efficient. These special characters are also known as globbing patterns.
Commonly Used Wildcards

Wildcard	Meaning
*	Matches any characters
?	Matches any single character
[characters]	Matches any character within the specified set
[!characters]	Matches any character not within the specified set
[[:class:]]	Matches any character belonging to the specified class

Common Character Classes

Character Class	Meaning
[:alnum:]	Matches any alphanumeric character
[:alpha:]	Matches any alphabetic character
[:digit:]	Matches any numerical character
[:lower:]	Matches any lowercase letter
[:upper:]	Matches any uppercase letter

Wildcards simplify file selection for complex operations. Below are some examples of wildcard patterns and what they match:

Pattern	Matches
	All files
g	Any file starting with "g"
b.txt	Files starting with "b" and ending with .txt
Data???	Files starting with "Data" followed by exactly three characters
[abc]	Files starting with either "a", "b", or "c"
BACKUP.[0-9][0-9][0-9]	Files starting with "BACKUP." followed by exactly three numbers

Creating Directories with mkdir The mkdir command allows users to create new directories efficiently. It follows this syntax:

You can create multiple directories simultaneously:

This command will generate three separate directories named dir1, dir2, and dir3.
Essential File and Directory Operations in Linux
Introduction Managing files and directories efficiently is a crucial aspect of working with Linux. While graphical interfaces make basic operations easier, the command-line tools provide unmatched power and flexibility for handling complex tasks.
This article covers essential file manipulation commands (cp, mv, rm, ln) and explores their useful options, practical examples, and important considerations.
Copying Files and Directories with cp The cp command is used to copy files and directories in different ways: Copy a single file: Copies item1 to item2. If item2 exists, it is overwritten.
Copy multiple items into a directory: Copies several files or directories into the specified directory.
Common Options for cp

Option	Meaning
-a, --archive	Preserve file attributes (ownership, permissions) during copying.
-i, --interactive	Ask for confirmation before overwriting an existing file.
-r, --recursive	Copy directories and their contents recursively.
-u, --update	Only copy files that don’t exist or are newer in the destination.
-v, --verbose	Show detailed progress messages during copying.

Practical cp Examples Moving and Renaming Files with mv The mv command is used to move files between locations or rename them. Move or rename a file: Moves item1 to item2, deleting the original.
Common Options for mv

Option	Meaning
-i, --interactive	Ask for confirmation before overwriting a file.
-u, --update	Move only newer files to the destination.
-v, --verbose	Display detailed progress messages.

Practical mv Examples Removing Files and Directories with rm The rm command permanently deletes files and directories. Use with caution! Delete a file: Removes the specified file.
Common Options for rm

Option	Meaning
-i, --interactive	Ask for confirmation before deleting a file.
-r, --recursive	Recursively delete directories and their contents.
-f, --force	Ignore errors and delete without prompting.
-v, --verbose	Show progress messages as deletion occurs.

Practical rm Examples Creating Links with ln The ln command is used to create hard or symbolic links. Create a hard link: Create a symbolic link: Creates a shortcut (link) that references the original file or directory (item).
Hard vs. Symbolic Links

Feature	Hard Link	Symbolic Link
File association	Directly points to data	References the file’s path
Cross-partition support	No	Yes
Survives file deletion	Yes	No

Symbolic links were introduced in Linux to overcome the limitations of hard links. They function by creating a special type of file that contains a text pointer to the referenced file or directory, much like shortcuts in Windows—though they existed in Unix systems long before Windows implemented them.
This article explores symbolic links, broken links, and provides a hands-on guide to file manipulation commands such as mkdir, cp, and mv.
Understanding Symbolic Links A symbolic link behaves like the referenced file itself: Writing to a symbolic link affects the original file. Deleting a symbolic link does not remove the original file. If the target file is deleted, the symbolic link remains but points to nothing—this is called a broken link.
Many Linux distributions display broken symbolic links in different colors, such as red, when using ls to help identify them easily.
Creating a Test Environment (Playground) To experiment safely with file manipulation commands, let’s create a dedicated directory:
Copying Files with cp Now, let's copy a system file (passwd) into our playground directory using the cp command:
This will display: Using cp with Additional Options Displays: If a file already exists, cp overwrites it without any warnings! To prompt before overwriting, use the interactive mode: Pressing y overwrites the file; pressing n leaves it unchanged.
Moving and Renaming Files with mv Since passwd isn’t playful, let’s rename it: Now, let’s move fun between directories: This allows us to move the file back and forth easily.
Moving Directories Now, let’s move an entire directory using mv: If dir2 already exists, dir1 is moved inside dir2. If dir2 did not exist, mv would have renamed dir1 to dir2.
Restoring the Playground Hard and symbolic links are essential features in Linux for managing files efficiently. Hard links refer to the same inode as the original file, while symbolic links store the path to the file, making them more flexible.
This article explains how to create hard and symbolic links and explores how file operations like rm and mv affect them.
Creating Hard Links To test hard links, let's create multiple references to the same file (fun): Now, we have four instances of the file fun, all pointing to the same inode.
Verifying Hard Links with ls -li Result: Both files have the same inode number, confirming they are actually the same file.
Creating Symbolic Links Unlike hard links, symbolic links have fewer restrictions: Can reference files across different partitions Can reference directories
Creating Symbolic Links in Linux In the above examples, the symbolic link stores only the file path, and ls -l shows: The symbolic link points to ../fun, meaning the target file is located one directory above.
Using Absolute vs. Relative Paths You can create symbolic links using absolute paths or relative paths: Using relative paths is better because moving directories won't break the links.
Deleting Files and Links with rm Now, let's remove hard and symbolic links to see their effects. After removal, the link count drops from 4 to 3, meaning one reference has been deleted.
Deleting the Original File and Its Effect on Symbolic Links After deletion, ls -l highlights the symbolic link in red or marks it as broken: Now, the symbolic link remains but points to a non-existent file.
Cleaning Up Broken Symbolic Links and Directories This removes all broken links and directories