A robust C-based client-server application that enables multiple clients to concurrently upload and download files while maintaining data consistency through reader-writer locks.

• Concurrent File Operations: Multiple clients can simultaneously access the server
• Reader-Writer Lock Implementation: Ensures data consistency during file operations
• Chunked File Transfer: Files are transferred in chunks for efficient memory usage
• Bi-directional Transfer: Supports both upload and download operations
• Network-safe Implementation: Handles network byte ordering and connection issues gracefully

• Implements a multi-threaded server architecture
• Uses pthread library for thread management
• Implements custom reader-writer locks for file access control
• Handles multiple client connections concurrently
• Buffer size: 128 bytes
• Buffer capacity: 8 chunks

• Provides a command-line interface for file operations
• Supports upload and download commands
• Chunk size: 1024 bytes
• Implements robust error handling

• GCC compiler
• POSIX-compliant operating system (Linux/Unix)
• pthread library

To compile the server:

gcc -o server server.c -pthread

To compile the client:

gcc -o client client.c

./server

./client

1. Upload a file:

upload <local_filename> <remote_filename>

2. Download a file:

download <remote_filename> <local_filename>

• Uses a mutex-based reader-writer lock implementation
• Prevents write-write and read-write conflicts
• Allows multiple simultaneous readers
• Writers have priority to prevent starvation

• Files are transferred in chunks to manage memory efficiently
• Network byte ordering is handled for cross-platform compatibility
• Robust error handling for network disconnections and I/O errors

• Graceful handling of client disconnections
• Proper cleanup of resources
• Comprehensive error messages for debugging
• Protection against buffer overflows

• Maximum filename length: 256 characters
• Fixed chunk sizes for transfer
• Server runs on local network only

Feel free to submit issues and enhancement requests.

This project is open source and available under the MIT License.