Look up DLEXT instead of assuming .so

ruby_dlext.patch

diff --git a/ruby/Makefile.am b/ruby/Makefile.am
index f605188..d28d77b 100644
--- a/ruby/Makefile.am
+++ b/ruby/Makefile.am
@@ -21,6 +21,8 @@ generator_built = \
 	ext/guestfs/_guestfs.c \
 	bindtests.rb
 
+DLEXT := $(shell $(RUBY) -rrbconfig -e "puts RbConfig::CONFIG['DLEXT']")
+
 EXTRA_DIST = \
 	$(generator_built) \
 	Rakefile.in \
@@ -38,7 +40,7 @@ CLEANFILES = \
 	ext/guestfs/*~ \
 	ext/guestfs/extconf.h \
 	ext/guestfs/_guestfs.o \
-	ext/guestfs/_guestfs.so \
+	ext/guestfs/_guestfs.$(DLEXT) \
 	ext/guestfs/mkmf.log \
 	ext/guestfs/Makefile
 
@@ -59,7 +61,7 @@ install:
 	$(MKDIR_P) $(DESTDIR)$(RUBY_LIBDIR)
 	$(MKDIR_P) $(DESTDIR)$(RUBY_ARCHDIR)
 	$(INSTALL) -p -m 0644 $(srcdir)/lib/guestfs.rb $(DESTDIR)$(RUBY_LIBDIR)
-	$(INSTALL) -p -m 0755 ext/guestfs/_guestfs.so $(DESTDIR)$(RUBY_ARCHDIR)
+	$(INSTALL) -p -m 0755 ext/guestfs/_guestfs.$(DLEXT) $(DESTDIR)$(RUBY_ARCHDIR)
 
 TESTS = run-bindtests run-ruby-tests
 
diff --git a/ruby/Rakefile.in b/ruby/Rakefile.in
index 94a25fd..1dfc600 100644
--- a/ruby/Rakefile.in
+++ b/ruby/Rakefile.in
@@ -40,9 +40,11 @@ end
 PKG_NAME='@PACKAGE_NAME@'
 PKG_VERSION='@PACKAGE_VERSION@'
 
+DLEXT=RbConfig::CONFIG['DLEXT']
+
 EXT_CONF='@abs_builddir@/ext/guestfs/extconf.rb'
 MAKEFILE='@builddir@/ext/guestfs/Makefile'
-GUESTFS_MODULE='@builddir@/ext/guestfs/_guestfs.so'
+GUESTFS_MODULE="@builddir@/ext/guestfs/_guestfs.#{DLEXT}"
 GUESTFS_SRC='@srcdir@/ext/guestfs/_guestfs.c'
 
 CLEAN.include [ "@builddir@/ext/**/*.o", GUESTFS_MODULE,