The situation is :-
I have a parent process that has PTRACE control of a child process. If the child process is in a system call, perhaps waiting on a key press, and it receives a signal then it is stopped and the parent is informed of the signal. So far so good. When I then resume the child process, the system decrements the PC by 2 so as to restart the system call.

The question :-
The decrementing of the PC upon resuming the process didn't happen in Linux 2.6.9xxx but does happen in 2.6.18xxx. Can anyone tell me in what version this change was made, or how do I find that out ?