From owner-freebsd-hackers@freebsd.org  Mon Jan  8 16:55:26 2018
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From: "Rodney W. Grimes" <freebsd-rwg@pdx.rh.CN85.dnsmgr.net>
Message-Id: <201801081655.w08GtO3D022568@pdx.rh.CN85.dnsmgr.net>
Subject: Re: Is it considered to be ok to not check the return code of close(2)
 in base?
In-Reply-To: <5A5399AA.9020309@grosbein.net>
To: Eugene Grosbein <eugen@grosbein.net>
Date: Mon, 8 Jan 2018 08:55:24 -0800 (PST)
CC: Eric van Gyzen <eric@vangyzen.net>, Brooks Davis <brooks@freebsd.org>,
 Alan Somers <asomers@freebsd.org>, Yuri <yuri@rawbw.com>,
 Ian Lepore <ian@freebsd.org>,
 Freebsd hackers list <freebsd-hackers@freebsd.org>
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> 08.01.2018 23:13, Eric van Gyzen wrote:
> 
> > Right, which is the reason such bugs are hard to diagnose.  Optionally
> > killing the process on close->EBADF would help find buggy code when
> > another thread did NOT re-open the file descriptor between the two close
> > calls.
> 
> Wouldn't "close(f); assert(errno != EBADF);" be better?

Or even
#ifdef DEBUG_CLOSE
#define close(f)	close(f); assert(errno != EBADF);
#endif

Then the people that want to go chasing these errors can,
and the rest of us are untouched.


-- 
Rod Grimes                                                 rgrimes@freebsd.org