diff --git a/ChangeLog b/ChangeLog
index 2101890a94..c53391f80c 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Wed Mar 21 17:01:55 2012  NAKAMURA Usaku  <usa@ruby-lang.org>
+
+	* test/ruby/test_io.rb (TestIO#test_pos_with_getc): added.
+	  see [Bug #6179][ruby-core:43518]
+
 Mon Mar 19 17:18:51 2012  Shugo Maeda  <shugo@ruby-lang.org>
 
 	* enumerator.c (lazy_flat_map_func): convert the block value to
diff --git a/test/ruby/test_io.rb b/test/ruby/test_io.rb
index b08e0753bf..a3ac12765c 100644
--- a/test/ruby/test_io.rb
+++ b/test/ruby/test_io.rb
@@ -1357,6 +1357,28 @@ class TestIO < Test::Unit::TestCase
     end
   end
 
+  def test_pos_with_getc
+    bug6179 = '[ruby-core:43497]'
+    t = make_tempfile
+    open(t.path, "w") do |f|
+      f.write "0123456789"
+    end
+
+    open(t.path, "r") do |f|
+      assert_equal 0, f.pos
+      assert_equal '0', f.getc
+      assert_equal 1, f.pos
+      assert_equal '1', f.getc
+      assert_equal 2, f.pos
+      assert_equal '2', f.getc
+      assert_equal 3, f.pos
+      assert_equal '3', f.getc
+      assert_equal 4, f.pos
+      assert_equal '4', f.getc
+    end
+  end
+
+
   def test_sysseek
     t = make_tempfile