In a web app, via handleSpecialURL, I launch a thread, which launches a Curl request with curlsMBS and performMT.
In the “finished” event of the curlsMBS object, I launch a new thread, which launches a new Curl request with performMT. it seems to work well.
But is it safe to launch a new CURL request in the “finished” event of another Curl request? Or is it better to launch a timer in the “finished” event to start the new request than a second later, for example?
Thats perfectly fine. You are separating the request from the event loop of the parent request by starting a new thread, so a timer would not make a real difference in terms of use safety. Like you said, things that can get you into trouble include reusing a socket from inside one of its events or getting into an endless event loop. Both will not happen with your approach.