What is File Handling in C++?

File handling in C++ refers to the process of reading from and writing to files using file streams. In C++, files are considered to be external storage that allows programs to store data permanently or retrieve data that was previously stored. By handling files, a C++ program can create, open, read, write, and manipulate files for various purposes, such as data storage, configuration, or logging.

File handling allows your program to interact with files on disk instead of relying solely on the program’s internal memory. This is crucial when working with large amounts of data or when you want the data to persist between program executions.

What are Files and Why Do We Need File Handling?

Files are collections of data that are stored on external storage devices, such as hard drives, SSDs, or cloud storage. There are two main categories of files:

• Text files: These are files that store data as plain text (human-readable). Each character is typically stored as a sequence of bytes, and the data can be opened and read using a text editor.
• Binary files: These files store data in a binary format, which is not human-readable. The data is stored as a series of 0s and 1s, and it’s typically more efficient for storing complex data structures, images, videos, or other non-textual data.

File handling is essential for several reasons:

• Persistence: Data stored in files is not lost when the program ends. This is useful for saving user progress, logging information, or maintaining records.
• Data Exchange: Files enable programs to exchange data with each other or with other systems (e.g., CSV, XML, JSON, etc.).
• Large Data Storage: Files allow you to store and process large datasets that cannot fit entirely in memory.

Different Types of Files: Text Files, Binary Files, etc.

1. Text Files:
   • Format: Text files are readable by humans and are often used for storing simple data like logs, configurations, and documents.
   • Structure: Data in a text file is stored as a sequence of characters (e.g., letters, numbers, and symbols). Each line is typically separated by a newline character.
   • Examples: .txt, .csv, .html, .xml
2. Binary Files:
   • Format: Binary files are used for storing data in non-readable formats, which may include images, videos, or compiled data. These files store data in the same format used by the computer internally.
   • Structure: Data is stored as sequences of bits (0s and 1s), and specific encoding schemes (like UTF-8 for text or custom binary formats for complex data structures) are used.
   • Examples: .dat, .bin, .exe, .jpg
3. Other Specialized File Types:
   • CSV Files: Comma-separated values (CSV) are commonly used to store tabular data. They are a form of text file, but the data is organized into columns and rows.
   • JSON, XML, and YAML: These are text-based formats used for structured data storage, often in applications where data needs to be exchanged between systems or persisted in a structured format.