Path: utzoo!utgpu!jarvis.csri.toronto.edu!cs.utexas.edu!swrinde!zaphod.mps.ohio-state.edu!usc!snorkelwacker!spdcc!ima!haddock!karl
From: karl@haddock.ima.isc.com (Karl Heuer)
Newsgroups: comp.lang.c
Subject: Re: typedef names
Message-ID: <15709@haddock.ima.isc.com>
Date: 20 Jan 90 03:14:54 GMT
References: <253@usblues.UUCP> <26449@stealth.acf.nyu.edu> <1990Jan19.181655.24096@utzoo.uucp> <YZhuprK00Vsa4O07JO@andrew.cmu.edu>
Reply-To: karl@haddock.ima.isc.com (Karl Heuer)
Organization: Interactive Systems, Cambridge, MA 02138-5302
Lines: 21

In article <YZhuprK00Vsa4O07JO@andrew.cmu.edu> bader+@andrew.cmu.edu (Miles Bader) writes:
>karl@haddock.ima.isc.com (Karl Heuer) writes:
>> Likewise, you should probably not use _t for your own typedefs, because
>> POSIX reserves this entire class for use in <sys/types.h>.
>
>Now that's an incredibly stupid thing to do, given the large number of people
>who already do use _t suffixes.

Well, let me rephrase it.  If you're *not* using <sys/types.h>, then you're
safe; there are only a finite number of _t names reserved outside of that
header (e.g. size_t).  If you *are* using <sys/types.h> in a program intended
to be portable, then you'd better not use any of the _t namespace, because the
implementation is permitted to have nonstandard extensions visible as long as
they use that spelling.  (E.g., ushort_t.)

I think this is better than the old method, where there was no guarantee at
all about the namespace of <sys/types.h>, and one vendor would typedef ushort
while another would do u_short, the end result being that both names are
reserved and neither is usable.

Karl W. Z. Heuer (karl@haddock.isc.com or ima!haddock!karl), The Walking Lint