Mercurial > hg > xemacs-beta
diff man/emodules.texi @ 880:beddd25fe24a
[xemacs-hg @ 2002-06-24 22:00:17 by youngs]
2002-06-17 Jerry James <james@xemacs.org>
* emodules.texi (Loading other Modules): Describe why we do not
use RTLD_GLOBAL.
2002-06-17 Jerry James <james@xemacs.org>
* sysdll.c: Remove RTLD_GLOBAL initialization.
* sysdll.c (dll_open): Do not use RTLD_GLOBAL.
author | youngs |
---|---|
date | Mon, 24 Jun 2002 22:00:25 +0000 |
parents | 7d972c3de90a |
children | 2b58b7fd831c |
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--- a/man/emodules.texi Mon Jun 24 10:01:22 2002 +0000 +++ b/man/emodules.texi Mon Jun 24 22:00:25 2002 +0000 @@ -483,6 +483,20 @@ then their parents will also fail to load. This does not include previous successful calls to @code{emodules_load} at the top level. +@strong{Warning:} Modules are @emph{not} loaded with the +@code{RTLD_GLOBAL} flag. The practical upshot is that individual +modules do not have access to each other's C symbols. One module cannot +make a C function call to a function defined in another module, nor can +it read or set a C variable in another module. All interaction between +modules must, therefore, take place at the Lisp level. This is by +design. Other projects have attempted to use @code{RTLD_GLOBAL}, only +to find that spurious symbol name clashes were the result. Helper +functions often have simple names, increasing the probability of such a +clash. If you really need to share symbols between modules, create a +shared library containing those symbols, and link your modules with +that library. Otherwise, interactions between modules must take place +via Lisp function calls and Lisp variables accesses. + @node Using ellcc, Defining Functions, Anatomy of a Module, Top @chapter Using @code{ellcc} @cindex @code{ellcc}