Re: terminate applications

["Randy Brukardt" <randy@rrsoftware.com>]

"Marin David Condic" <nobody@noplace.com> wrote in message
news:3F1BD666.6040506@noplace.com...
> Yes, a clean shutdown is desirable. I suspect where I have my program
> hanging trying to terminate the environment task is within some OS fault
> - or "feature". But so long as the user has a control-C key on his
> keyboard, there exists the possibility of a direct headshot to a
> program, so it must be possible to do that from under program control.

For what it's worth, Janus/Ada's runtime tries to trap as many such possible
"headshots" and cause a clean shutdown. We definitely try to trap control-C
(which doesn't always work for some reason that I've never understood).

That has it's roots in our compiler, where it was traditional to kill long
compilations with control-C if they were finding too many errors or some
other problem came up. But a straight kill would leave temporary files and
(worse) partially written object files which could confuse the Make tool.
Thus, we tried very hard to insure that compiles were never aborted without
the clean-up code running.

Of course, there is no recourse to a kill -9 or pulling the plug. But those
should be a really last resort. (Of course, I've never seen a program with a
correct runtime hang when it was aborted. I had some programs do that when
the runtime was screwed up, but no other time. If checks are not suppressed,
I'd consider it a bug.)

                             Randy.