# UDP Server in C
This is a simple UDP server program written in C. It binds to `127.0.0.1` on port `5501` and listens for incoming datagrams.
## Files
- `main.c` : The UDP server code.
## Requirements
- GCC or any C compiler
- Linux or macOS (or WSL on Windows)
## How to Compile and Run
1. **Compile:**
```bash
gcc main.c -o udp_server
- Run:
./udp_server
It will start and wait for incoming UDP packets.
Code Explanation (Brief)
- socket() – creates a UDP socket.
- bind() – binds to
127.0.0.1:5501. - recvfrom() – receives data from any UDP client.
- printf() – prints the received message.
Example Client (Testing)
To test quickly, use netcat as a UDP client:
echo "Hello Server" | nc -u 127.0.0.1 5501
Or write your own simple C client to send a datagram to port 5501.
Reference
UDP Client-Server Program in C
Notes
- Change
127.0.0.1to0.0.0.0to bind on all interfaces. - Always handle errors in production-grade code (
if (sockfd < 0) { perror("socket failed"); exit(1); }etc).
Feel free to modify and extend this as needed for your networking practice or system programming portfolio.