Subject: Re: SA_SIGINFO notes
To: Matt Thomas <matt@3am-software.com>
From: Christos Zoulas <christos@zoulas.com>
List: tech-kern
Date: 10/07/2003 13:00:31
On Oct 7,  9:45am, matt@3am-software.com (Matt Thomas) wrote:
-- Subject: Re: SA_SIGINFO notes

| 
| On Tuesday, October 7, 2003, at 09:34 AM, Christos Zoulas wrote:
| > A simpler way, is to have trapsignal assert that si_code > 0,
| > so that we can simply test for si_code > 0. In this case we
| > really don't care if the signal came from the kernel or userland
| > as long as we can tell if the signal was generated by a trap
| > or not.
| 
| That won't work.  For arithmetic faults, both vax and powerpc use
| a ksi_code of 0 since it's quite difficult to figure out which
| fault actually happened.

That is why I am suggesting that trapsignal() will assert that
ksi_code > 0. Then the vax and powerpc, they will have to be fixed
to return SI_UNKNOWN or something which is > 0. Maybe 0xff?

christos