[Python-Dev] Trap SIGSEGV and SIGFPE

[Jeffrey Yasskin]

On Thu, Dec 11, 2008 at 1:34 AM, Victor Stinner
<victor.stinner at haypocalc.com> wrote:
> But if -as many people wrote-
> Python is totally broken after a segfault, it is maybe not a good idea :-)

While it's true that after a segfault or unexpected longjmp, there are
no guarantees whatsoever about the state of the python program, the
program will often just happen to work, and there are at least some
programs I've worked on that would rather take the risk in order to
try to shut down gracefully. For example, an interactive app may want
to give the user a chance to save her (not necessarily corrupted) work
into a new file rather than unconditionally losing it. Or a webserver
might want to catch the segfault, finish replying to the other
requests that were in progress at the time, maybe reply to the request
that caused the segfault, and then restart. Yes there's a possibility
that the events around the segfault exposed some secret internal data
(and they may do so even without segfaulting), but when the
alternative is not replying to the users at all, this may be a risk
the app wants to take. It would be nice for Python to at least expose
the option so that developers (who are consenting adults, remember)
can make their own decisions. It should _not_ be on by default, but
something like sys.dangerous_turn_C_crashes_into_exceptions() would be
useful.

Jeffrey