Building an OTP-Based Login System in C

Introduction

Introduce the concept of an OTP-based login system and its importance in enhancing security for user authentication.

Code Overview

Explain the structure of the code and its key components:

• User Structure: Define a structure to store user phone numbers, OTPs, and OTP verification status.

• Functions: Implement functions for user signup, OTP generation, and login authentication.

Functions

Signup

Allows users to sign up by entering their phone number.

void signup() {
    // Implementation for user signup
}

Generate OTP

Generates a random 4-digit OTP for a user.

void generateOTP(struct User *user) {
    // Implementation for OTP generation
}

Login

Enables users to log in using their phone number and OTP verification.

int login() {
    // Implementation for user login
}

Main Function

Contains the menu-driven interface for user interaction:

int main() {
    // Main function code
}

Explanation

• Signup: Allows users to register by entering their phone numbers.

• OTP Generation: Generates a random 4-digit OTP for user verification.

• Login: Verifies user login using the generated OTP.

Conclusion

Summarize the functionality of the OTP-based login system and its benefits in enhancing security for user authentication.

Final Thoughts

Encourage readers to explore advanced authentication mechanisms and security practices for robust user authentication systems.

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This structure provides a clear explanation of the OTP-based login system code and its functionality, making it informative and accessible for readers interested in user authentication in C programming.

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