add the libdir to the ltdl lib search path

* libguile/Makefile.am (libpath.h): Fix pkgdatadir, pkglibdir, and
  pkgincludedir entries. Add a new define, SCM_LIB_DIR.

* libguile/dynl.c (sysdep_dynl_init): Add the libdir to the libltdl
  search path. Should fix
  http://thread.gmane.org/gmane.lisp.guile.bugs/4289/focus=4296 -- that
  is, it should allow guile to be invoked from whereever it is
  installed, without munging LTDL_LIBRARY_PATH or the like variables.

  There is a trick though -- during the build, we don't want to be
  looking in the $libdir for loadable modules. So as with
  GUILE_SYSTEM_PATH, we have GUILE_SYSTEM_LTDL_PATH.

* meta/uninstalled-env.in: Set GUILE_SYSTEM_LTDL_PATH to "" when
  building.

1 files changed, 15 insertions, 0 deletions

diff --git a/libguile/dynl.c b/libguile/dynl.c
index dc98e7d17..6b13e65a9 100644
--- a/libguile/dynl.c
+++ b/libguile/dynl.c
@@ -48,6 +48,7 @@ maybe_drag_in_eprintf ()
 #include <string.h>
 
 #include "libguile/_scm.h"
+#include "libguile/libpath.h"
 #include "libguile/dynl.h"
 #include "libguile/smob.h"
 #include "libguile/keywords.h"
@@ -113,7 +114,21 @@ sysdep_dynl_func (const char *symb, void *handle, const char *subr)
 static void
 sysdep_dynl_init ()
 {
+  char *env;
+
   lt_dlinit ();
+
+  env = getenv ("GUILE_SYSTEM_LTDL_PATH");
+  if (env && strcmp (env, "") == 0)
+    /* special-case interpret system-ltdl-path=="" as meaning no system path,
+       which is the case during the build */
+    ; 
+  else if (env)
+    lt_dladdsearchdir (env);
+#ifdef SCM_LIB_DIR
+  else
+    lt_dladdsearchdir (SCM_LIB_DIR);
+#endif
 }
 
 scm_t_bits scm_tc16_dynamic_obj;