libftp: A Simple C++ Library

Introduction to deniskovalchuk/libftp Library

1. Project Overview

• Name: libftp
• Language: C++
• Type: FTP Client Library
• Goal: To provide a simple and easy-to-use C++ interface for performing FTP operations such as connecting, logging in, uploading, downloading, and listing directories.

2. Core Features

This project provides a FTPClient class that encapsulates common FTP operations:

• Connect to an FTP server
• Username/password login
• Change working directory (CWD)
• List directory contents (LIST)
• Upload files (STOR)
• Download files (RETR)
• Delete files (DELE)
• Create/delete directories

3. Usage Example

According to its README and code, the usage is very straightforward:

#include "ftp_client.h" // Include header file
#include <iostream>

int main() {
    try {
        // 1. Create FTP client and connect to server
        FTPClient ftp("ftp.example.com", 21); // Address and port

        // 2. Login
        ftp.login("username", "password");

        // 3. List current directory
        std::cout << "Directory listing:\n";
        auto files = ftp.list();
        for (const auto & file : files) {
            std::cout << file << std::endl;
        }

        // 4. Download file
        ftp.download("remote_file.txt", "local_file.txt");

        // 5. Upload file
        ftp.upload("local_file.txt", "remote_file_copy.txt");

        // 6. Disconnect
        ftp.quit();
    }
    catch (const std::exception & e) {
        std::cerr << "FTP Error: " << e.what() << std::endl;
    }

    return 0;
}

4. Technical Details

• Dependencies: This project directly uses the underlying Berkeley Sockets API (Winsock on Windows) for network communication. This means it has no external library dependencies (other than the system’s built-in socket library), but needs to link ws2_32.lib on Windows.
• Compilation: Since it is a project with separated header and source files, you need to compile ftp_client.cpp into your project and include ftp_client.h.
• Protocol: Implements the standard FTP protocol (plain text transmission). Does not support FTPS or SFTP, so the transmitted username, password, and file contents are unencrypted.

5. Advantages

• Easy to use: The API design is simple and quick to get started.
• Lightweight: Small codebase with no third-party dependencies.
• Clear header files: Interface definitions are clear.

6. Limitations and Considerations

• Security: Only supports insecure FTP. When used in production environments or public networks, usernames, passwords, and data may be intercepted. Not recommended for transmitting sensitive information.
• Limited functionality: Only implements the most basic FTP commands, lacking advanced features (such as fine control over passive/active modes, proxy support, asynchronous operations, etc.).
• Activity level: The last commit to this project was several years ago, and it may no longer be actively maintained.
• Error handling: Although exceptions are used, robustness in complex network environments needs to be validated.
• Platform compatibility: Although cross-platform sockets are used, attention should still be paid to differences in compilation and linking across different operating systems (especially Windows and Linux).

Comparison with libcurl

Feature	deniskovalchuk/libftp	libcurl
FTP/FTPS/SFTP	Only FTP (insecure)	Supports FTP, FTPS, SFTP
Protocol Support	Only FTP	HTTP, HTTPS, FTP, SFTP, SCP, SMTP, IMAP, …
Dependencies	Only system Sockets	Requires installation of libcurl library
Maturity	Niche, personal project	Industry-grade, used by countless projects
Security	Low (plain text)	High (supports encryption)
Feature richness	Basic functionality	Extremely rich (proxy, authentication, redirection, cookies, etc.)
Recommendation Level	Learning/simple internal tools	Preferred for production environments

Conclusion

deniskovalchuk/libftp is a real but very niche C++ FTP client library. It is suitable for the following scenarios:

• Learning purposes: To study how to implement the FTP protocol using C++ and Sockets.
• Internal tools: To add FTP functionality to a simple tool in a trusted intranet environment without wanting to introduce a large library.
• Rapid prototyping: When a minimal FTP upload/download functionality is needed for demonstration.