Hello-httpd is a project mainly written in C, it's free.
My first web server.
make ./hello 8080 &
telnet 127.0.0.1 8080 Trying 127.0.0.1... Connected to localhost. Escape character is '^]'. GET / HTTP/1.0
HTTP/1.0 200 OK Content-type: text/html
<!DOCTYPE html>
This is index.html.
Connection closed by foreign host.