OSX breakage

OSX breakage

[Mario Lassnig]

Hi,

the recent revno 106533 broke compilation on OSX Lion for me, because 
environ is not defined in unistd.h (possibly this is the case for 
previous versions of OSX as well).


The remedy (to include at the appropriate time and place):

#include <crt_externs.h>
#define environ (*_NSGetEnviron())

Thanks,
Mario

Re: OSX breakage

[Paul Eggert]

On 11/28/11 07:36, Mario Lassnig wrote:
> #include <crt_externs.h>
> #define environ (*_NSGetEnviron())

That's weird, since the previous code didn't do that.
Why not use "extern char **environ;", which the
previous code used, and which presumably worked?

Re: OSX breakage

[Eli Zaretskii]

> Date: Mon, 28 Nov 2011 16:36:25 +0100
> From: Mario Lassnig <mario@lassnig.net>
> 
> The remedy (to include at the appropriate time and place):
> 
> #include <crt_externs.h>
> #define environ (*_NSGetEnviron())

Is there really no system header on OS X that declares `environ'?  I'm
surprised.

If there really isn't, and we need to use #ifdef, I'm inclined to use
"extern char **environ;".  What would be a MAC OS X specific symbol to
use with such an ifdef?

Re: OSX breakage

[Mario Lassnig]

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>>/  Date: Mon, 28 Nov 2011 16:36:25 +0100/
>>/  From: Mario Lassnig<address@hidden>/
>>/  /
>>/  The remedy (to include at the appropriate time and place):/
>>/  /
>>/  #include<crt_externs.h>/
>>/  #define environ (*_NSGetEnviron())/

>Is there really no system header on OS X that declares `environ'?  I'm
>surprised.

That's correct. And even system headers do it like this, probably
there's some magic in the background to work with ns-dragndrop and the likes.

Mario@shodan:/usr/include$ grep -r " environ " *
X11/Xw32defs.h:#  define environ     _environ
apache2/modperl_perl_includes.h:#   define environ (*_NSGetEnviron())
architecture/i386/fpu.h: *     #define environ (*_NSGetEnviron())

>If there really isn't, and we need to use #ifdef, I'm inclined to use
>"extern char **environ;".  What would be a MAC OS X specific symbol to
>use with such an ifdef?

That would be

#ifdef __APPLE__


Thanks,
Mario

-- 
Mario Lassnig
CERN PH-ADP-DDM 1-R-022
CH-1211 Geneve 23
mario.lassnig@cern.ch
+41 22 76 71268



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Re: OSX breakage

[Paul Eggert]

On 11/28/11 09:47, Eli Zaretskii wrote:
> Is there really no system header on OS X that declares `environ'?  I'm
> surprised.

That's the old, old Unix tradition, alas.  It's not just OS X.
The "right" way to fix it is to declare "extern char **environ;"
if it's not already declared.  There's a Gnulib module for that,
which I can look into -- it puts the declaration into a substitute
unistd.h if unistd.h doesn't already declare it.

Re: OSX breakage

[Randal L. Schwartz]

>>>>> "Eli" == Eli Zaretskii <eliz@gnu.org> writes:

>> Date: Mon, 28 Nov 2011 16:36:25 +0100
>> From: Mario Lassnig <mario@lassnig.net>
>> 
>> The remedy (to include at the appropriate time and place):
>> 
>> #include <crt_externs.h>
>> #define environ (*_NSGetEnviron())

Eli> Is there really no system header on OS X that declares `environ'?  I'm
Eli> surprised.

Indeed, there's not.  OSX is BSD is old-school.  environ is "just there".

-- 
Randal L. Schwartz - Stonehenge Consulting Services, Inc. - +1 503 777 0095
<merlyn@stonehenge.com> <URL:http://www.stonehenge.com/merlyn/>
Smalltalk/Perl/Unix consulting, Technical writing, Comedy, etc. etc.
See http://methodsandmessages.posterous.com/ for Smalltalk discussion

Re: OSX breakage

[Chong Yidong]

Paul Eggert <eggert@cs.ucla.edu> writes:

> On 11/28/11 09:47, Eli Zaretskii wrote:
>> Is there really no system header on OS X that declares `environ'?  I'm
>> surprised.
>
> That's the old, old Unix tradition, alas.  It's not just OS X.
> The "right" way to fix it is to declare "extern char **environ;"
> if it's not already declared.  There's a Gnulib module for that,
> which I can look into -- it puts the declaration into a substitute
> unistd.h if unistd.h doesn't already declare it.

As Eli pointed out in the discussion on bug#10155, there is already code
in lib/unistd.in.h that apparently ought to handle this, but itsn't
working.

I will delay the pretest until this problem is fixed.

Re: OSX breakage

[Paul Eggert]

On 11/28/11 21:00, Chong Yidong wrote:
> As Eli pointed out in the discussion on bug#10155, there is already code
> in lib/unistd.in.h that apparently ought to handle this, but itsn't
> working.

I'll send a proposed patch to that discussion.

Re: OSX breakage

[Ashish SHUKLA]

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Mario Lassnig writes:
> Hi,

> the recent revno 106533 broke compilation on OSX Lion for me, because
> environ is not defined in unistd.h (possibly this is the case for
> previous versions of OSX as well).

It's also broken on FreeBSD, as well.

-- 
Ashish SHUKLA

“The death rate is the same for us as for anybody… one person, one
death, sooner or later.” (Robert A. Heinlein, "Tunnel in the Sky",
1955)

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Re: OSX breakage

[Carsten Mattner]

On Tue, Nov 29, 2011 at 12:45 PM, Ashish SHUKLA <wahjava.ml@gmail.com> wrote:
> Mario Lassnig writes:
>> Hi,
>
>> the recent revno 106533 broke compilation on OSX Lion for me, because
>> environ is not defined in unistd.h (possibly this is the case for
>> previous versions of OSX as well).
>
> It's also broken on FreeBSD, as well.

Seems to be fixed by Chong in revno 106554 on Darwin, but a typo
has been introduced in the comment: Shouln't unisted.h be unistd.h?

Re: OSX breakage

[Ashish SHUKLA]

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Ashish SHUKLA writes:
> Mario Lassnig writes:
>> Hi,

>> the recent revno 106533 broke compilation on OSX Lion for me, because
>> environ is not defined in unistd.h (possibly this is the case for
>> previous versions of OSX as well).

> It's also broken on FreeBSD, as well.

Fixed on FreeBSD after installing r106556.

Thanks
-- 
Ashish SHUKLA

“Never underestimate the power of human stupidity.” (Robert
A. Heinlein, 1973)

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