diff --git a/ChangeLog b/ChangeLog
index e3adaa1a39..566114343b 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+Tue Dec 23 16:22:41 2008  Tanaka Akira  <akr@fsij.org>
+
+	* io.c (rb_io_inspect): show fd number if there is no pathname.
+
 Tue Dec 23 15:48:55 2008  NAKAMURA Usaku  <usa@ruby-lang.org>
 
 	* tool/file2lastrev.rb: shouldn't use single quote in shell's command
diff --git a/io.c b/io.c
index 632e3500c9..93855f917b 100644
--- a/io.c
+++ b/io.c
@@ -1353,15 +1353,29 @@ rb_io_inspect(VALUE obj)
 {
     rb_io_t *fptr;
     const char *cname;
+    char fd_desc[256];
+    const char *path;
     const char *st = "";
 
     fptr = RFILE(rb_io_taint_check(obj))->fptr;
-    if (!fptr || NIL_P(fptr->pathv)) return rb_any_to_s(obj);
     cname = rb_obj_classname(obj);
-    if (fptr->fd < 0) {
-	st = " (closed)";
+    if (!fptr || NIL_P(fptr->pathv)) {
+        if (fptr->fd < 0) {
+            path = "";
+            st = "(closed)";
+        }
+        else {
+            snprintf(fd_desc, sizeof(fd_desc), "fd %d", fptr->fd);
+            path = fd_desc;
+        }
     }
-    return rb_sprintf("#<%s:%s%s>", cname, RSTRING_PTR(fptr->pathv), st);
+    else {
+        path = RSTRING_PTR(fptr->pathv);
+        if (fptr->fd < 0) {
+            st = " (closed)";
+        }
+    }
+    return rb_sprintf("#<%s:%s%s>", cname, path, st);
 }
 
 /*
diff --git a/test/ruby/test_io.rb b/test/ruby/test_io.rb
index d00c0a3f7c..e0350452d5 100644
--- a/test/ruby/test_io.rb
+++ b/test/ruby/test_io.rb
@@ -705,7 +705,7 @@ class TestIO < Test::Unit::TestCase
 
   def test_inspect
     with_pipe do |r, w|
-      assert(r.inspect =~ /^#<IO:0x[0-9a-f]+>$/)
+      assert(r.inspect =~ /^#<IO:fd \d+>$/)
       assert_raise(SecurityError) do
         safe_4 { r.inspect }
       end