extconf.rb in openbabel-2.3.1.4

- old
+ new

@@ -17,10 +17,17 @@
     puts `curl -L -d use_mirror=netcologne "http://downloads.sourceforge.net/project/openbabel/openbabel/#{ob_num_ver}/openbabel-#{ob_num_ver}.tar.gz" | tar xz`
   end
   Dir.chdir ob_main_dir do
     puts "Configuring OpenBabel"
     puts `cmake #{ob_main_dir} -DCMAKE_INSTALL_PREFIX=#{lib_dir}`
-    unless File.exists?(`which obabel`.chomp)
+    openbabel_libs = false
+    openbabel_libs = true if `ldconfig -p`.split("\n").grep(/openbabel/)
+    unless openbabel_libs
+      ENV["LD_LIBRARY_PATH"].split(":").each do |dir|
+        openbabel_libs = true unless Dir[File.join(dir,"*libopenbabel*")].empty?
+      end
+    end
+    unless openbabel_libs
       puts "OpenBabel not installed. Compiling sources."
       puts `make`
       puts `make install`
     end
   end