From owner-cvs-lib  Mon May 19 04:01:59 1997
Return-Path: <owner-cvs-lib>
Received: (from root@localhost)
          by hub.freebsd.org (8.8.5/8.8.5) id EAA14942
          for cvs-lib-outgoing; Mon, 19 May 1997 04:01:59 -0700 (PDT)
Received: from godzilla.zeta.org.au (godzilla.zeta.org.au [203.2.228.19])
          by hub.freebsd.org (8.8.5/8.8.5) with ESMTP id EAA14917;
          Mon, 19 May 1997 04:01:29 -0700 (PDT)
Received: (from bde@localhost) by godzilla.zeta.org.au (8.8.5/8.6.9) id UAA11773; Mon, 19 May 1997 20:56:47 +1000
Date: Mon, 19 May 1997 20:56:47 +1000
From: Bruce Evans <bde@zeta.org.au>
Message-Id: <199705191056.UAA11773@godzilla.zeta.org.au>
To: cvs-all@FreeBSD.ORG, cvs-committers@FreeBSD.ORG, cvs-lib@FreeBSD.ORG,
        peter@FreeBSD.ORG
Subject: Re: cvs commit: src/lib/libutil libutil.h
Sender: owner-cvs-lib@FreeBSD.ORG
X-Loop: FreeBSD.org
Precedence: bulk

>  Modified files:
>    lib/libutil          libutil.h 
>  Log:
>  Now I really understand the reason for the style.9 rule about not having
>  visible type names in prototypes in user space headers.  libutil.h
>  generates warnings with -Wall over the use of "const char *ttyname".
>  It's lucky it wasn't a #define conflict.
>  Is a single '_' prefix acceptable? or does it need to be two?

Two '_'s are only useful for extra defense against broken programs
that #define reserved names.  Two are unnecessary for the same reason
that two are unnecessary for most of the members of the FILE struct -
the opening parentheses in prototypes changes the scope much like the
the opening brace in a struct declaration.

Why did -Wall generate warnings?  It takes -Wshadow to get a warning for
the ttyname in <libutil.h> shadowing the one in <unistd.h>

Bruce