To-Do List Application

A simple command-line To-Do List application written in C that allows users to add, view, edit, and delete tasks. Tasks are stored persistently in a file named todo.txt.

Features

• Add new tasks with unique IDs
• View all existing tasks
• Edit tasks by specifying the task ID
• Mark tasks as completed (delete by ID)
• Persistent storage using binary file operations

How to Compile and Run

1. Save the source code in a file, for example, todo.c.
2. Compile the program using GCC or any C compiler:

gcc todo.c -o todo

3. Run the compiled executable:

./todo

Usage

On running the program, you will see the following menu:

----- To Do List ----
1. Add task
2. View all tasks
3. Edit Task by Entering ID
4. Mark Task as completed
5. Exit
Enter your choice:

• Add task: Enter a unique task ID and description.
• View all tasks: Lists all tasks with their IDs.
• Edit task: Modify the description of an existing task by ID.
• Mark task as completed: Deletes the task by ID.
• Exit: Terminates the program.

File Storage

Tasks are stored in a binary file todo.txt. Each record consists of a struct with an ID and a task description.

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Future Improvements / Suggestions

• Add priority levels and sort tasks by priority.
• Implement search by keywords.
• Use status (Pending/Completed) instead of deleting tasks.
• Store tasks in text formats like JSON or CSV.
• Add undo for delete/edit actions.
• Improve error handling and input validation.
• Ensure cross-platform compatibility.
• Create a GUI version for better usability.