Re: [boost] boost.filesystem on HPUX

From: Thomas Matelich (matelich_at_[hidden])
Date: 2005-06-20 16:54:48

On 6/20/05, Toon Knapen <toon.knapen_at_[hidden]> wrote:
> Caleb Epstein wrote:
> 
> > Well, there is code in
> > libs/filesystem/src/operations_posix_windows.cpp that attempts to
> > detect if it is being compiled with multi-threading enabled:
> >
> > #     if defined(_POSIX_THREAD_SAFE_FUNCTIONS) \
> >       && defined(_SC_THREAD_SAFE_FUNCTIONS) \
> >       && (_POSIX_THREAD_SAFE_FUNCTIONS+0 >= 0)
> >
> > Presumably aCC sets these macros incorrectly, or this code is not
> > correct.  Maybe the check should be for >0?
> 
> 
> Since somebody suggested that _REENTRANT is defined on HP when the '-mt'
> flag is used, what about only adding adding following to this #if
> 
>   #     if defined(_POSIX_THREAD_SAFE_FUNCTIONS) \
>         && defined(_SC_THREAD_SAFE_FUNCTIONS) \
>         && (_POSIX_THREAD_SAFE_FUNCTIONS+0 >= 0)
>         || (defined(__HP_aCC) && defined(_REENTRANT))
> 

I don't use boost build, but I thought the existing ifdef block seemed
like it should work.  I don't know much about HPUX on Itanium, but I
went grepping on my HP 11i box, and found the
_POSIX_THREAD_SAFE_FUNCTIONS define in /usr/include/sys/unistd.h. 
Then I remembered that to use the new posix friendly APIs on 11i, you
need a -D_POSIX_C_SOURCE=199506L.  I'd bet that if you added that to
your build, things would work a lot more nicely.  I think that define
is only contra-indicated if you're still trying to use CMA threads
(which is not a good idea).

If you do end up needing a modification of the define block above, I'd
recommend __hpux rather than __HP_aCC since this is a platform issue
rather than a compiler issue.