PHWinfo - Afficher un message - Throwing exceptions in a unix signal handler. Good idea?

10/06/2008, 08h47

On 2008-06-09 17:45:04 +0200, thagor2008@googlemail.com said:

> On Jun 9, 4:26 pm, Pete Becker <p...@versatilecoding.com> wrote:
>> From the C99 standard: "If the signal occurs other than as the result
>
> That C, not C++.

It is both. C++ gets its specification for signal and raise from the C
standard.

>
>> So, unless the signal came from a call to abort or raise, the behavior
>> is undefined.
>
> It may be undefined from the point of view of the C standard , but not
> from the unix standard otherwise there'd be no point using signals -
> every time a handler was called you'd have to hold your breath and
> hope the program didn't crash!

Yes, that's correct.

>
> I'm only interested in the specific combination of C++ exceptions and
> signal handlers since once stores the stack and one forces an unwind.
> Are compilers smart enough to know to pop the signal handler stack
> first and return to where the signal occured before unwinding the
> stack for the exception is the question.
>
>

If you're interested in platform-specific behavior, you need to ask on
a newsgroup that discusses your platform. In standard C++, the behavior
is undefined.

--
Pete
Roundhouse Consulting, Ltd. (www.versatilecoding.com) Author of "The
Standard C++ Library Extensions: a Tutorial and Reference
(www.petebecker.com/tr1book)

10/06/2008, 08h47	#9
Pete Becker Messages: n/a Hébergeur:	Re: Throwing exceptions in a unix signal handler. Good idea? On 2008-06-09 17:45:04 +0200, thagor2008@googlemail.com said: > On Jun 9, 4:26 pm, Pete Becker <p...@versatilecoding.com> wrote: >> From the C99 standard: "If the signal occurs other than as the result > > That C, not C++. It is both. C++ gets its specification for signal and raise from the C standard. > >> So, unless the signal came from a call to abort or raise, the behavior >> is undefined. > > It may be undefined from the point of view of the C standard , but not > from the unix standard otherwise there'd be no point using signals - > every time a handler was called you'd have to hold your breath and > hope the program didn't crash! Yes, that's correct. > > I'm only interested in the specific combination of C++ exceptions and > signal handlers since once stores the stack and one forces an unwind. > Are compilers smart enough to know to pop the signal handler stack > first and return to where the signal occured before unwinding the > stack for the exception is the question. > > If you're interested in platform-specific behavior, you need to ask on a newsgroup that discusses your platform. In standard C++, the behavior is undefined. -- Pete Roundhouse Consulting, Ltd. (www.versatilecoding.com) Author of "The Standard C++ Library Extensions: a Tutorial and Reference (www.petebecker.com/tr1book)