A way to build and install libpthread as 1:1 as well as M:N?

[Daniel Eischen]

On Mon, 19 Jul 2004, Robert Watson wrote:

> On Sun, 18 Jul 2004, Daniel Eischen wrote:
> 
> > > The issue here is my keeping everything in sync and making sure testing is
> > > reproduceable.  If I'm manually building and installing threading
> > > libraries, I'm likely to screw it up.  I was hoping for a mechanism in
> > > buildworld/installworld so that it all happens automatically, reducing the
> > > chances of user error, stale library versions, etc.
> > 
> > Well, like I said, if we can agree on a place to put the 1:1 version and
> > what to call it, we can make it happen.  My suggestion is to keep the
> > libraries named the same, install them in different places, and use
> > LD_LIBRARY_PATH to switch between them. 
> > 
> > Should I just do it, or is more discussion needed? 
> 
> Other than the need for something like it, I don't have much opinion on
> the mechanism by which it's accomplished.  I think that what you suggest
> sounds pretty reasonable to me.  I'd be fine with a libpthread11, a
> lib/foo/libpthread, or whatever makes the most sense to you.  I guess
> maybe I have a slight preference for libpthread11, but agree that the
> benefits of being able to use LD_LIBRARY_PATH are substantial and probably
> more important than the slight asthetic preference.

Well, it didn't add much to the library to allow either 1:1 or M:N.
Here's a patch that lets you run in 1:1 mode if LIBPTHREAD_SYSTEM_SCOPE
is defined in the environment.  I'm not stuck on its name, so feel
free to suggest something else.

  http://people.freebsd.org/~deischen/kse/libpthread.diffs

Warning (*), you can still force 1:1 mode if you build the library
with -DSYSTEM_SCOPE_ONLY, so be sure to remove this when rebuilding
libpthread.

(*) I think it's still useful for archs that don't run in M:N yet.

-- 
Dan Eischen