Add warnings about environment variables

These variables all get read by GTK 2.x as well, which makes
them dangerous at best.

diff --git a/docs/reference/gtk/running.sgml b/docs/reference/gtk/running.sgml
index 6a4911a2e5083e0d230ad66770bf86f0cfc3032a..b2b894601b3e540818258ca4af3fedd19f6d768e 100644 (file)
--- a/docs/reference/gtk/running.sgml
+++ b/docs/reference/gtk/running.sgml
@@ -199,6 +199,10 @@ additional environment variables.
   <para>
     A list of modules to load. Note that GTK+ also allows to specify modules to load via a commandline option (<option>--gtk-module</option>) and with the <literal>gtk-modules</literal> setting.
   </para>
+  <warning>
+    Note that this environment variable is read by GTK+ 2.x too,
+    which may not have the same set of modules available for loading.
+  </warning>
 </formalpara>
 
 <formalpara>
@@ -211,7 +215,7 @@ additional environment variables.
     modules, file system backends and print backends. If the path to
     the dynamically loaded object is given as an absolute path name,
     then GTK+ loads it directly.
-    Otherwise, GTK+ goes in turn through the directories in GTK_PATH,
+    Otherwise, GTK+ goes in turn through the directories in <envar>GTK_PATH</envar>,
     followed by the directory <filename>.gtk-3.0</filename> in the user's
     home directory, followed by the system default directory,
     which is <filename><replaceable>libdir</replaceable>/gtk-3.0/modules</filename>.
@@ -241,6 +245,12 @@ additional environment variables.
     The components of GTK_PATH are separated by the ':' character on
     Linux and Unix, and the ';' character on Windows.
   </para>
+  <warning>
+    Note that this environment variable is read by GTK+ 2.x too, which
+    makes it unsuitable for setting it system-wide (or session-wide),
+    since doing so will cause either GTK+ 2.x applications or GTK+ 3
+    applications to see incompatible modules.
+  </warning>
 </formalpara>
 
 <formalpara>
@@ -268,6 +278,12 @@ additional environment variables.
     The <filename>immodules.cache</filename> file is generated by the
     <command>gtk-query-immodules-3.0</command> utility.
   </para>
+  <warning>
+    Note that this environment variable is read by GTK+ 2.x too, which
+    makes it unsuitable for setting it system-wide (or session-wide),
+    since doing so will cause either GTK+ 2.x applications or GTK+ 3
+    applications to see the wrong list of IM modules.
+  </warning>
 </formalpara>
 
 <formalpara>