## signals.api
# Compiled by:
# src/lib/std/src/standard-core.sublib# These are the two basic interfaces to the run-time system signals support.
# The interface covers the basic signals operations, plus a small collection
# of standard signals that should be portable to non-UNIX systems.
#
# The original design of this system is discussed in:
#
# Asynchronous Signals in Standard ML
# John H Reppy 1990 19p
# http://mythryl.org/pub/pml/asynchronous-signals-in-standard-ml-reppy-1990-19p.ps
# This API is implemented in:
#
# src/lib/std/src/nj/runtime-signals.pkg#
# it is also 'include'-d in the anonymous api in
#
# src/lib/std/src/nj/runtime-signals-guts.pkgapi Runtime_Signals {
#
eqtype Signal;
Signal_Action
= IGNORE
| DEFAULT
| HANDLER (Signal, Int, fate::Fate(Void)) -> fate::Fate( Void )
;
list_signals: Void -> List( Signal );
#
# List the signals supported by this version
signal_name: Signal -> String; # Return the name of a signal.
get_signal_by_name: String -> Null_Or( Signal );
#
# Return the signal with the corresponding name.
# Return NULL if no such signal exists.
set_signal_handler: (Signal, Signal_Action) -> Signal_Action;
#
# Set the handler for a signal, returning the previous action.
override_signal_handler: (Signal, Signal_Action) -> Signal_Action;
#
# If a signal is not being ignored, then set the handler.
#
# Returns the previous handler: If IGNORE, then
# the current handler is still IGNORE.
get_signal_handler # Get the current action for the given signal
:
Signal -> Signal_Action;
Signal_Mask
= MASK_ALL
| MASK List(Signal)
;
mask_signals: Signal_Mask -> Void;
#
# Mask the specified set of signals.
#
# Signals that are not IGNORED
# will be delivered when unmasked.
#
# Calls to mask_signals nest on a
# per-signal basis.
unmask_signals: Signal_Mask -> Void;
#
# Unmask the specified signals. The unmasking of a signal that is
# not masked has no effect.
masked: Void -> Signal_Mask;
#
# return the set of masked signals; the value MASK[] means that
# no signals are masked.
pause: Void -> Void;
#
# sleep until the next signal; if called when signals are masked,
# then signals will still be masked when pause returns.
# These signals should be supported even on non-UNIX platforms.
#
interrupt_signal: Signal; # interactive interrupt -- SIGINT
alarm_signal: Signal; # interval timer signal -- SIGALRM
terminate_signal: Signal; # termination -- SIGTERM.
#
heapcleaning_done_signal: Signal; # Pseudosignal generated internally by runtime for hypothetical Mythryl app code. I can find no current use of this. -- 2012-03-20 CrT
}; # api Signals
## COPYRIGHT (c) 1995 AT&T Bell Laboratories.
## Subsequent changes by Jeff Prothero Copyright (c) 2010-2012,
## released under Gnu Public Licence version 3.