🛠️ Project #1: SSU-Cleanup

🌟 Overview

SSU-Cleanup is a file management and organization utility for Linux systems. Its core function is to organize files within a specified directory based on their extensions.

The project aims to:

• Understand shell principles by implementing new commands using system functions.
• Adapt to standard and file I/O by using system data structures, system calls, and libraries.
• Improve system programming skills by implementing the directory structure using a linked list.

Category	Details
Program Name	ssu_cleanup
Environment	Linux system
Scope	Sub-paths under the user's home directory (/home/user_id)
Prompt	학번) (e.g., 20230000))
Constraint	ABSOLUTELY NO USE of system() function (results in 0 points)

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💻 Built-in Commands

The ssu_cleanup program includes four built-in commands:

1. tree

Displays the directory and file structure recursively in a tree format.

• Usage: tree (DIR_PATH) [OPTION]...
• Arguments:
  • <DIR_PATH>: The starting directory path (supports relative and absolute paths).
  • [OPTION]: Can be -s, -p, or omitted. Multiple options can be used simultaneously.
• Options:
  • (none): Basic recursive tree display. Directory names end with a slash (/).
  • -s: Includes the size of each file and directory.
  • -p: Includes the permissions of each file and directory.
  • -sp: Includes both permissions and size.
• Output: Must display the total number of directories and files at the end.

2. arrange

Organizes files within a directory based on their extensions. The organized files are copied to an extension-specific subdirectory (e.g., txt/, c/) inside the result directory.

• Usage: arrange (DIR_PATH) [OPTION]
• Arguments:
  • <DIR_PATH>: The directory to be organized (supports relative and absolute paths).
  • [OPTION]: Optional. Includes -d, -t, -x, -e.
• Result Directory: By default, it creates <DIR_PATH>_arranged in the current working directory.
• Duplicate File Handling: If files with the same name are found within the directory to be organized, a prompt must appear, offering the following choices:
  • 0. select [num]
  • 1. diff [num1] [num2]
  • 2. vi [num]
  • 3. do not select
• Options:
  • -d <output_path>: Specifies <output_path> as the destination directory for the organized files.
  • -t <seconds>: Only arranges files that were modified more than <seconds> seconds ago.
  • -x <exclude_path1, ...>: Arranges the directory excluding files inside the specified exclude directories.
  • -e <extension1, ...>: Arranges files that only have the specified extensions.

3. help

Outputs the usage (description) of the program's built-in commands.

• Usage: help [COMMAND]

4. exit

Terminates the currently running ssu_cleanup program.

• Usage: exit

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⚠️ Exception Handling (Deductions)

Command	Exception Condition	Deduction (Points)
General	Enter key only: Re-output prompt.	2
	Input other than built-in commands: Output help usage, then re-output prompt.	3
tree	Invalid path (non-existent) as first argument: Output Usage, re-output prompt.	2
	Path exceeds max length (4096B) or name exceeds max length (256B).	2
	Path is not a directory or is outside the user's home directory.	2
	Absolute path is outside $HOME (~): Output <input path> is outside the home directory, re-output prompt.	2
	Invalid option as second argument: Output Usage, re-output prompt.	2
arrange	No first argument: Output Usage, re-output prompt.	3
	Path exceeds max length (4096B) or name exceeds max length (256B).	2