Re: lib/41085: sigaction returns EINVAL instead of -1

[David Laight <david%l8s.co.uk@localhost>]

The following reply was made to PR lib/41085; it has been noted by GNATS.

From: David Laight <david%l8s.co.uk@localhost>
To: gnats-bugs%NetBSD.org@localhost
Cc: lib-bug-people%netbsd.org@localhost, gnats-admin%netbsd.org@localhost,
        netbsd-bugs%netbsd.org@localhost, matteo%beccati.com@localhost
Subject: Re: lib/41085: sigaction returns EINVAL instead of -1
Date: Sat, 28 Mar 2009 12:24:58 +0000

 On Sat, Mar 28, 2009 at 04:45:02AM +0000, David Holland wrote:
 >  
 >  I've looked over the kernel and libc code involved and I don't see any
 >  plausible way for it to mix the return value and error code, unless
 >  something Xen-specific is causing the carry flag (which distinguishes
 >  error returns from real return values) to get cleared in the low-level
 >  code on the way back from the system call.
 
 Or somehow some Linux system call code is being used/assumed...
 Where, instead of using the carry flag, small negative return values
 are taken as errno values.
 
        David
 
 -- 
 David Laight: david%l8s.co.uk@localhost