From: Garance A Drosihn <drosih@...>
Date: 2003-07-26T12:59:21+09:00
Subject: Re: ruby 1.8.0 preview4

At 7:11 AM +0900 7/26/03, Brian Candler wrote:
>On Sat, Jul 26, 2003, Yukihiro Matsumoto wrote:
>  > |readline.c: In function `readline_readline':
>>  |readline.c:51: warning: implicit declaration of function `isatty'
>>
>>  Do you mean isatty(3) is not declared in <unistd.h> on FreeBSD?
>
>No, it is declared there. I think the problem is here:
>
>#ifdef HAVE_UNISTD_H
>#include <unistd.h>
>#endif
>
>but config.h (via ruby.h) has not been included at that point,
>so unistd.h is not being included.

FreeBSD does spend some effort to minimize namespace pollution,
such that symbols from one include library (such as unistd.h)
will not show up when some other library is included, unless
the standards say those symbols must show up.  And even then,
we try to only bring in the symbols that must be brought in,
and not the entire include file.

So, in other OS's you could very well bring in the symbols
you want from unistd.h (or even *all* of unistd.h) even if
you never explicitly #include it.

-- 
Garance Alistair Drosehn            =   gad@gilead.netel.rpi.edu
Senior Systems Programmer           or  gad@freebsd.org
Rensselaer Polytechnic Institute    or  drosih@rpi.edu