These operations allow to mark thread as a single-stepping one.
This allows to i.a.:
- single step and emit a signal (PT_SETSTEP & PT_CONTINUE)
- single step and trace syscall entry and exit (PT_SETSTEP & PT_SYSCALL)
The former is useful for debuggers like GDB or LLDB. The latter can be used
to singlestep a usermode kernel. These examples don't limit use-cases of
this interface.
Define PT_*STEP only for platforms defining PT_STEP.
Add new ATF tests setstep[1234].
These ptrace(2) operations first appeared in FreeBSD.
Sponsored by <The NetBSD Foundation>