pub const DEFAULT_BACKEND_CAPABILITIES: BackendCapabilities;Expand description
The capabilities a Config has before the host prepares it for the
backend that runs it: ptrace’s, the backend Detcore’s own tests use, except
that eight facts stay off (supports_blocked_wait_signal_interruption and
the four split out of it, which set_kernel_signal_facts clears
together, delivers_preemption_timer_events,
runs_guest_code_between_injections, reports_sigreturns). Until
supports_blocked_wait_signal_interruption,
delivers_preemption_timer_events and
runs_guest_code_between_injections became backend capabilities they were
Config fields that only the host set, for the backend it had selected,
and were false otherwise; a configuration nobody prepared keeps that
behaviour, and the four readings of the first with it. A configuration
nobody prepared cannot know that sigreturns are reported, so that is off
too (the DBT runtime’s standalone
fallback starts from these). reports_kernel_child_exit_signals keeps
ptrace’s value, as reports_child_exit_publication does: it took over the
child-exit ledger’s gates from that field, so such a configuration behaves
as before. The host copies the running backend’s own answer over all of
these before a run.