Re: Dynamic Loading for multiple files?

From: Erick Gallesio <eg_at_kaolin.unice.fr>
Date: Wed, 28 Sep 1994 14:33:43 +0000

>
> Is there a way to get multiple files to be dynamically loadable?
>
> I want to use the functionality in Extensions/hash.c to write another
> dynamically-loaded C file. Since hash.c is also statically linked in,
> I can do this, but later, I will want to have a *lot* of C files which
> all get dynamically linked into stk.
>
> Right now, I get this:
>
> bolverk:stk
> Welcome to the STk interpreter version 2.1
> Copyright (C) 1993, 1994 Erick Gallesio - I3S - CNRS / UNSA <eg_at_unice.fr>
> STk> (load "hash.so")
> #[undefined]
> STk> (load "timers.so")
> ld.so: call to undefined procedure _make_hash_table from 0xef6fb114
>
> What am I doing wrong?

I don't know, but it seems that ld.so is unable to resolve this kind of call.
I don't know how to resolve this problem (without using static linking of
course). Is thers someone on the mailing list who knows how to use functions
which are dynamically loaded in a dynamic file?

DEC Alpha dlopen(2) states something like:

  void *dlopen(filename, mode)
  char *filename;
  int mode;

  ...

  If mode is RTLD_LAZY, then the runtime loader does symbol resolution only
  as needed. Typically, this means that the first call to a function in the
  newly loaded library will cause the resolution of the address of that func-
  tion to occur. If mode is RTLD_NOW, then the runtime loader must do all
  symbol binding during the dlopen call. The dlopen function returns a han-
  dle that is used by dlsym or dlclose call. If there is an error, a NULL
  pointer is returned.

Is RTLD_LAZY, the solution of this problem? (on sunos4, it seems however that
we have no choice since its is stated in the manual that mode must always be
1).



                -- Erick
Received on Wed Sep 28 1994 - 14:33:44 CET