How to write a Lighttpd plugin to do live streaming - streaming

Question

I'd like to write a Lighttpd plugin to do streaming..
so far i duplicate the client_socket (con->fd) in the function 'mod_strm_handle_physical'. So that I can send streaming data thru it in a child process. As for the main process, I set some status to the connection struct to tell the server not to close this conneciton.
Here are how i did in the 'mod_strm_handle_physical' function:
URIHANDLER_FUNC(mod_strm_handle_physical)
{
if(con->uri.path->ptr)
{
if(!strcmp("/abcd", con->uri.path->ptr))
{
// change Content-Type
response_header_overwrite(srv, con
, CONST_STR_LEN("Content-Type")
, CONST_STR_LEN("application/octet-stream"));
con->http_status = 200;
con->file_finished = 0; // not to close the connection
con->response.keep_alive = 1;
int dup_fd = dup(con->fd); // duplicate the client-socket
int child = fork();
if(child>0)
return HANDLER_FINISHED;
else if(child==0)
{
send(dup_fd, STREAMING_DATA, LENGTH, 0);
close(dup_fd);
exit(0);
}
else
perror("fork()");
}
}
return HANDLER_GO_ON;
}
The problem is..
in this way, the server can do streaming and seems okay. However, the server cannot do more than one streaming at the same time. Is something I am doing wrong? I though the streaming job is out-process