re: lib/53495: sched_get_priority_max/sched_get_priority_min not returning useful values

[matthew green <mrg%eterna.com.au@localhost>]

The following reply was made to PR lib/53495; it has been noted by GNATS.

From: matthew green <mrg%eterna.com.au@localhost>
To: gnats-bugs%NetBSD.org@localhost
Cc: lib-bug-people%netbsd.org@localhost, gnats-admin%netbsd.org@localhost,
    netbsd-bugs%netbsd.org@localhost, Thomas Klausner <wiz%NetBSD.org@localhost>
Subject: re: lib/53495: sched_get_priority_max/sched_get_priority_min not returning useful values
Date: Fri, 03 Aug 2018 17:07:24 +1000

 >  This is not a bug. It works as intended.
 >  
 >  NetBSD behavior is compliant with POSIX and 3rd party program has to be
 >  fixed and handle the -1 case on its own, if there is need to distinguish
 >  error and unsupported, there is an option to reset errno and check it
 >  after the call.
 
 this makes no sense to me.  opengroup says:
 
    If unsuccessful, they shall return a value of -1 and set errno
    to indicate the error.
 
 so "-1" can not be a useful value by definition.  clearly our
 implementation needs to map between internal values and ones
 we return to these functions if "-1" is interanlly useful.
 
 it's also extremely awful to introduce more APIs that abuse errno
 like you suggest, and should not be done any time.
 
 
 .mrg.