How high-level languages use signals

Invoking a callable service involves setting up registers that are unique to the high-level language.

1. The RTL, using these callable services, sets up a SIR to receive control when a signal occurs.
2. The SIR procedure performs the necessary language linkages and POSIX functions to call the signal catcher procedure.
3. The signal catcher may return to the SIR.
4. The SIR performs the necessary language and POSIX functions to return to the interrupted procedure after the signal catcher returns.
5. The CSRL16J system service loads all registers and the PSW condition code and jumps to the instruction that was interrupted by the signal.