Subj : Re: Where to download a pthread library
To   : comp.programming.threads
From : Marcin 'Qrczak' Kowalczyk
Date : Wed Mar 30 2005 12:13 am

"David Schwartz" <davids@webmaster.com> writes:

>     The '-lpthread' flag is not a convention or standard at all. Many 
> platforms require more than just linking in an additional library, they need 
> compiler flags (like -D_REENTRANT) as well. The standard is '-pthread' to do 
> whatever is needed for both the compiler and linker to support pthreads. 
> FreeBSD was very slow to adopt this standard due to some confusion.
>
>     You should look it up in your documentation.

What should a portable program do? Let's say it want to use pthreads
if they are supported, but it will work without them too (with less
functionality).

Here is what I currently do:

   AC_CHECK_HEADERS([pthread.h], [
      AC_CHECK_LIB(pthread, pthread_create, [
         KO_HAVE_PTHREADS=yes
         KO_PTHREAD_LINK=-lpthread
      ])
   ])

How this can be improved? Should I define _REENTRANT? Should I look in
another library too?

If pthread functions are stubs which do nothing or throw errors
(I've heard some systems provide such versions if no additional thread
library is linked), I want to treat this case as if pthreads were not
available.

-- 
   __("<         Marcin Kowalczyk
   \__/       qrczak@knm.org.pl
    ^^     http://qrnik.knm.org.pl/~qrczak/

.