Re: wish list for rsh

[Brian May <bmay@csse.monash.edu.au>]

>>>>> "Brandon" == Brandon S Allbery KF8NH <allbery@kf8nh.apk.net> writes:

    Brandon> It's a sort-of-Unixized port of OS/2 shared libraries.
    Brandon> So you need to use OS/2-style import files to link one
    Brandon> shared library against another, linking goes much more
    Brandon> easily if you have OS/2-style export files, and all
    Brandon> symbols must be resolved at shared library build time,
    Brandon> among other oddities compared to most Unixes.

Yuck. Initially I thought Win3.0 DLLs were a very good feature of
windows, but since they were ported to OS/2, and probably
AIX. However, since then I have learnt about shared libraries under
most versions of Unix ;-)

    Brandon> Also, shared objects that work fine on every other system
    Brandon> I've built them on, regardness of weirdness (such as the
    Brandon> shared library version of netpbm from the libgr package),
    Brandon> build on AIX but programs using them dump core on
    Brandon> startup.  I suspect this means static data in shared
    Brandon> libraries behaves strangely.  (I *hope* it doesn't use
    Brandon> the OS/2 default of "static data is shared between
    Brandon> processes using the shared library"...).

Probably.

    Brandon> In any case, the Cyrus SASL libraries refuse to build
    Brandon> properly on AIX as distributed, and while I can get
    Brandon> something (of unknown functionality) if I update it to
    Brandon> use the latest libtool, you then have to use that same
    Brandon> libtool version to link against SASL.

What version of libtool supports AIX?

Ok, I see the following in the libtool documentation:

Some platforms, such as AIX, do not even allow you this
flexibility. In order to build a shared library, it must be entirely
self-contained (that is, have references only to symbols that are
found in the .lo files or the specified -l libraries), and you need to
specify the -no-undefined flag. By default, libtool builds only static
libraries on these kinds of platforms.

not very good. Does AIX have any support for PAM (or similar)?

    Brandon> | In the past I have heard about a GNU project under
    Brandon> development from | GNU that will allow a static library
    Brandon> to be read at runtime like a | shared library[1] (for
    Brandon> platforms without good shared library support), | do you
    Brandon> think this would help?  +--->8

    Brandon> One can hope.  I do wish IBM would implement
    Brandon> Solaris/Linux-style shared libraries, though.

I think I might have stated that wrongly (although it was the
way I understood it at the time, so maybe I just cannot find
the reference again).

Anyway, from the libtool documentation at

http://www.gnu.org/software/libtool/manual.html#Dlpreopening:

"Libtool emulates -dlopen on static platforms by linking objects into
the program at compile time, and creating data structures that
represent the program's symbol table."

-- 
Brian May <bmay@csse.monash.edu.au>