[libmicrohttpd] How to get response back to requesting thread?

[Bob Furber]

|I realize this is not really a MHD issue, but, it is likely an issue 
your readers have encountered.||

I have a ||custom ||server [C] ||program ||on a Linux-Arm platform 
||which uses MHD ||as its||front end to receive and respond to http 
requests.| |||

Currently, each request is processed in its own thread ||to obtain the 
response||, with the processing code sandwiched inside a mutex to 
protect data from being altered by code in the main-loop ..which also 
accesses the same data. ||Think of the data as a home-baked database 
that is being altered by the main-loop AND by http requests.| |||

Dreaming in Technicolor, I would like to have all the data processing 
done in the main-loop. That is, request||s||would be transferred from 
the connection threads to the main-loop by means of some IPC ||FIFO 
||process such as a message queue or named pipe. ||My problem is||, I 
cannot figure out how the main-loop would get the response back to the 
requesting thread.||

Again, d||reaming in Technicolor, ||I would like to use some magic IPC 
process where the MHD thread would tag the request with a 
return_response_to_this_pid ||return address ||to allow the main loop to 
deliver the response messages addressed to the corresponding 
corresponding MHD_thread ...an IPC method along the lines of 
send_ipc_msg( message, receiving_pid ). | |||

Clues anybody?| I am not even sure how to ask the right question. ||