PULL request: allow signals up to SIGRTMAX

Hi together, for some time now I have a pull request open (https://github.com/php/php-src/pull/1457) where I want to introduce the two constants SIGRTMIN and SIGRTMAX and allow pcntl_signal() to register handlers for "real-time signals" (from SIGRTMIN to SIGRTMAX). From the signal manpage: > Unlike standard signals, real-time signals have no predefined meanings: the entire set of > real-time signals can be used for application-defined purposes. This allows cli applications/long running processes to communicate via signals without assigning unexpected meaning to the well-known lower (<SIGRTMIN) signals. From what I see in the source code, all other functions related to signals already handle signals in such a generic way that using real-time signals is possible without a problem except you can not safely know the actual values of SIGRTMIN and SIGRTMAX and you can not register a handler for them with pcntl_signal(). Is there a need to create an RFC for this change? Or can someone review it and maybe apply it? Thanks, Dennis