Windows/Linux File Downloader in C

A C program that demonstrates how to download a file over HTTP from a server using sockets. The program is cross-platform, working on both Windows and Linux systems.

Features

• Cross-platform support: Works on both Windows and Linux.
• Socket: Uses sockets to connect to a server and download a file.
• Minimal dependencies: Only standard C libraries and platform-specific socket libraries are used.

Requirements

Windows

• GCC (MinGW or similar)
• Winsock2 library (comes with Windows)

Linux

• GCC
• Standard POSIX libraries (usually included with most Linux distributions)

Building the Project

Windows

To build the program on Windows, use the following command:

gcc downloader.c -o downloader -g -Wextra -std=c11 -lws2_32

Linux

To build the program on Linux, use the following command:

gcc downloader.c -o downloader -g -Walloca -Wextra -Wall -fsanitize=address,undefined -std=c11

Usage

After compiling, you can run the program as follows:

./downloader

The program will connect to example.com and download the file located on remote server, saving it locally as downloaded_file.log.

Customization

• Hostname: The hostname to connect to is currently set to example.com.
• Path: The path to the file on the server is set to /file.txt.
• Port: The port used for the connection is 80 (HTTP).

You can customize these values by modifying the following lines in downloader.c:

const char *hostname = "example.com";
const char *path = "/file.txt";
const char *port = "80";

Platform-Specific Notes

Windows

The program uses Winsock2 for socket communication. Ensure that Winsock2 is initialized using WSAStartup() before any socket operations and cleaned up using WSACleanup() after all operations are done.

Linux

The program uses POSIX-compliant socket functions and does not require any special initialization or cleanup beyond the normal opening and closing of sockets.

Troubleshooting

• Socket Connection Issues: Ensure that the server you are trying to connect to is reachable and that the port is open.
• Compilation Errors: Make sure you are using GCC with the appropriate flags as described in the "Building the Project" section.
• File Writing Issues: Ensure that you have write permissions to the directory where the file will be saved.

Author

Max Base

License

This project is licensed under the GPL-3.0 License. See the LICENSE file for more details.

Copyright 2024, Max Base