File Operations and I/O

1. Introduction

From JavaScript File API to C File Operations

In JavaScript, file operations are typically asynchronous and handled through the File API or Node.js fs module. In C, file operations are synchronous and use low-level system calls, providing direct control over file handling.

💡 Key Concept: C file operations give you precise control over file I/O but require careful error handling and resource management.

2. Basic File Operations

3. File Modes and Operations

4. Error Handling and File Positioning

5. Binary File Operations

6. Common Pitfalls

• Not checking file open success: Always check if fopen() returns NULL
• Forgetting to close files: Always call fclose() to prevent resource leaks
• Buffer overflow: Ensure buffer size is sufficient for file operations
• File positioning errors: Use fseek() and ftell() carefully
• Binary vs text mode: Use appropriate mode for file type

7. Exercises

1. Write a program that copies one file to another, handling errors appropriately.
2. Create a function that reads a file line by line and counts the number of words.
3. Write a program that appends data to a log file with timestamps.

8. Performance Analysis

• C file operations are generally faster than JavaScript due to direct system calls
• Buffered I/O (fprintf, fscanf) is more efficient than character-by-character I/O
• Binary file operations are faster than text operations
• Proper error handling is crucial for robust file operations

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Summary: C file operations provide low-level control and high performance but require careful error handling and resource management. Understanding file modes, positioning, and binary operations is essential for system programming.