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Re: Help: Ada in NetBSD

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Okay, so another short blog post. This is going to be a bit of a fucking 
rant.

So... remember when I said that NetBSD expected a priority value of -1 
when using SCHED_ODER? And that that was not POSIX compilant? Well, 
after a nice conversation in #netbsd, it has been decided to escalate 
this matter into a PR/ML discussion. All that good :)

But the question on how does Linux work then? Remained... So I ran the 
ACATS suite with debugging symbols, recompilation and assertions to 
check. And guess what?

Let the code speak:


    else 

      Param.sched_priority := 0; 

      Result := 

      pthread_setschedparam 

      (T.Common.LL.Thread, 

       SCHED_OTHER, Param'Access); 

    end if; 


    pragma Assert (Result in 0 | EPERM | EINVAL); 

end Set_Priority;

So the Set_Priority function receives the Default_Priority value, which 
I think was 48. But when it goes into the actual branch, it knows that 
that default value is stupid and discards it (sets it to 0). That would 
be all nice and dandy, but here is the problem, 0 is a valid value 
because most OS/arches use it, there is no reason 0 is valid (as per POSIX).

And what really gets me is that Pragma... Whomever wrote it probably was 
getting errors and decided that that was fine. EPERM? EINVAL? Not my 
problem! No wonder there is a specific s-taprop__linux.adb...


So here we are. NetBSD is not POSIX compliant (min and max SCHED_OTHER 
priority is -1, which is an error code for the function that should 
return it), and Linux hardcodes it. Amazing, just amazing...


My solution? Email the NetBSD people. But that won't be enough. So I am 
thinking in patching the s-taprop__posix.adb file to try it with the 
default priority, if it fails, with 0, if it fails, with -1 for NetBSD...


Oh well... I thought that the state of GNAT was better... Anyhow, regards,
-- 
Fernando Oleo Blanco
https://irvise.xyz

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Help: Ada in NetBSD Fernando Oleo Blanco <irvise_ml@irvise.xyz> - 2021-08-29 13:06 +0200
  Re: Help: Ada in NetBSD Stephane Carrez <stephane.carrez@gmail.com> - 2021-08-29 06:19 -0700
    Re: Help: Ada in NetBSD Fernando Oleo Blanco <irvise_ml@irvise.xyz> - 2021-08-29 20:08 +0200
      Re: Help: Ada in NetBSD Simon Wright <simon@pushface.org> - 2021-08-29 19:25 +0100
        Re: Help: Ada in NetBSD Fernando Oleo Blanco <irvise_ml@irvise.xyz> - 2021-08-29 22:36 +0200
          Re: Help: Ada in NetBSD Stephane Carrez <stephane.carrez@gmail.com> - 2021-08-29 15:08 -0700
            Re: Help: Ada in NetBSD Simon Wright <simon@pushface.org> - 2021-08-30 08:37 +0100
            Re: Help: Ada in NetBSD Fernando Oleo Blanco <irvise_ml@irvise.xyz> - 2021-08-30 10:14 +0200
              Re: Help: Ada in NetBSD Fernando Oleo Blanco <irvise_ml@irvise.xyz> - 2021-08-30 12:24 +0200
                Re: Help: Ada in NetBSD Fernando Oleo Blanco <irvise_ml@irvise.xyz> - 2021-08-30 14:15 +0200
                Re: Help: Ada in NetBSD Fernando Oleo Blanco <irvise_ml@irvise.xyz> - 2021-08-30 20:49 +0200
                Re: Help: Ada in NetBSD Simon Wright <simon@pushface.org> - 2021-08-30 20:23 +0100
                Re: Help: Ada in NetBSD Fernando Oleo Blanco <irvise_ml@irvise.xyz> - 2021-09-01 11:44 +0200
                Re: Help: Ada in NetBSD Simon Wright <simon@pushface.org> - 2021-09-01 22:41 +0100
                Re: Help: Ada in NetBSD "Randy Brukardt" <randy@rrsoftware.com> - 2021-09-02 17:16 -0500
                Re: Help: Ada in NetBSD Simon Wright <simon@pushface.org> - 2021-09-03 21:18 +0100
  Re: Help: Ada in NetBSD Simon Wright <simon@pushface.org> - 2021-08-29 18:34 +0100
    Re: Help: Ada in NetBSD Fernando Oleo Blanco <irvise_ml@irvise.xyz> - 2021-08-29 19:45 +0200
  Re: Help: Ada in NetBSD "John R. Marino" <mfl-commissioner@marino.st> - 2021-09-01 06:28 -0700
    Re: Help: Ada in NetBSD Fernando Oleo Blanco <irvise_ml@irvise.xyz> - 2021-09-01 16:58 +0200
      Re: Help: Ada in NetBSD Fernando Oleo Blanco <irvise_ml@irvise.xyz> - 2021-09-17 19:36 +0200
        Re: Help: Ada in NetBSD Fernando Oleo Blanco <irvise_ml@irvise.xyz> - 2021-09-18 18:39 +0200
          Re: Help: Ada in NetBSD Fernando Oleo Blanco <irvise_ml@irvise.xyz> - 2021-09-22 22:05 +0200
            Re: Help: Ada in NetBSD Simon Wright <simon@pushface.org> - 2021-09-22 21:57 +0100
            Re: Help: Ada in NetBSD "Luke A. Guest" <laguest@archeia.com> - 2021-09-23 09:04 +0100
              Re: Help: Ada in NetBSD Kevin Chadwick <m8il1ists@gmail.com> - 2021-09-23 03:48 -0700
                Re: Help: Ada in NetBSD Fernando Oleo Blanco <irvise_ml@irvise.xyz> - 2021-09-23 19:01 +0200
              Re: Help: Ada in NetBSD Fernando Oleo Blanco <irvise_ml@irvise.xyz> - 2021-09-23 19:04 +0200
            Re: Help: Ada in NetBSD Fernando Oleo Blanco <irvise_ml@irvise.xyz> - 2021-09-23 21:53 +0200
              Re: Help: Ada in NetBSD Simon Wright <simon@pushface.org> - 2021-09-24 08:48 +0100
                Re: Help: Ada in NetBSD Fernando Oleo Blanco <irvise_ml@irvise.xyz> - 2021-09-24 11:44 +0200
    Re: Help: Ada in NetBSD Fernando Oleo Blanco <irvise_ml@irvise.xyz> - 2021-09-13 20:49 +0200
      Re: Help: Ada in NetBSD Dennis Lee Bieber <wlfraed@ix.netcom.com> - 2021-09-13 18:24 -0400
        Re: Help: Ada in NetBSD Fernando Oleo Blanco <irvise_ml@irvise.xyz> - 2021-09-17 19:19 +0200

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