diff --git a/contrib/10.readline/src/readline.c b/contrib/10.readline/src/readline.c
index 84f932bc..f9de7060 100644
--- a/contrib/10.readline/src/readline.c
+++ b/contrib/10.readline/src/readline.c
@@ -6,9 +6,8 @@
 forget to use the C++ extern "C" to get it to compile.
 */
 #include <editline/readline.h>
-#include <editline/history.h>
-#include <histedit.h>
 #include "picrin.h"
+#include "picrin/pair.h"
 #include "picrin/string.h"
 #include "picrin/port.h"
 
@@ -40,6 +39,67 @@ pic_rl_add_history(pic_state *pic)
   return pic_undef_value();
 }
 
+static pic_value
+pic_rl_stifle_history(pic_state *pic)
+{
+  int  i;
+  
+  pic_get_args(pic, "i", &i);
+
+  stifle_history(i);
+
+  return pic_undef_value();
+}
+
+static pic_value
+pic_rl_unstifle_history(pic_state *pic)
+{
+  pic_get_args(pic, "");
+
+  unstifle_history();
+  
+  return pic_undef_value();
+}
+
+static pic_value
+pic_rl_history_is_stifled(pic_state *pic)
+{
+  pic_get_args(pic, "");
+
+  return pic_bool_value(history_is_stifled());
+}
+
+static pic_value
+pic_rl_history_length(pic_state *pic)
+{
+  pic_get_args(pic, "");
+
+  return pic_int_value(history_length);
+}
+
+static pic_value
+pic_rl_where_history(pic_state *pic)
+{
+  pic_get_args(pic, "");
+
+  return pic_int_value(where_history());  
+}
+
+static pic_value
+pic_rl_history_get(pic_state *pic)
+{
+  int i;
+  HIST_ENTRY *e;
+
+  pic_get_args(pic, "i", &i);
+  
+  e = history_get(i);
+  if(!e)
+    pic_errorf(pic, "failed to get entry");
+
+  return pic_obj_value(pic_str_new_cstr(pic, e->line));
+}
+
 static pic_value
 pic_rl_clear_history(pic_state *pic)
 {
@@ -53,21 +113,72 @@ pic_rl_clear_history(pic_state *pic)
 static pic_value
 pic_rl_remove_history(pic_state *pic)
 {
-  int line;
+  int i;
 
-  pic_get_args(pic, "i", &line);
+  pic_get_args(pic, "i", &i);
 
-  remove_history(line);
+  remove_history(i);
+  
+  return pic_undef_value();
+}
+
+static pic_value
+pic_rl_read_history(pic_state *pic)
+{
+  char *filename;
+
+  pic_get_args(pic, "z", &filename);
+
+  if(read_history(filename))
+    pic_errorf(pic, "cannot read history file :%s", filename);
+  
+  return pic_undef_value();
+}
+
+static pic_value
+pic_rl_write_history(pic_state *pic)
+{
+  char *filename;
+
+  pic_get_args(pic, "z", &filename);
+
+  if(write_history(filename))
+    pic_errorf(pic, "cannot write history file:%s", filename);
+  
+  return pic_undef_value();
+}
+
+static pic_value
+pic_rl_truncate_file(pic_state *pic)
+{
+  char *filename;
+  int i;
+
+  pic_get_args(pic, "zi", &filename, &i);
+
+  history_truncate_file(filename, i);
   
   return pic_undef_value();
 }
 
 void
 pic_init_readline(pic_state *pic){
+  using_history();
   pic_deflibrary (pic, "(picrin readline)") {
     pic_defun(pic, "readline", pic_rl_readline);
+  }
+  pic_deflibrary (pic, "(picrin readline history)") {
     pic_defun(pic, "add-history", pic_rl_add_history);
+    pic_defun(pic, "stifle-history", pic_rl_stifle_history);
+    pic_defun(pic, "unstifle-history", pic_rl_unstifle_history);
+    pic_defun(pic, "history-stifled?", pic_rl_history_is_stifled);
+    pic_defun(pic, "history-length", pic_rl_history_length);
+    pic_defun(pic, "where-history", pic_rl_where_history);
+    pic_defun(pic, "history-get", pic_rl_history_get);
     pic_defun(pic, "clear-history", pic_rl_clear_history);
     pic_defun(pic, "remove-history", pic_rl_remove_history);
+    pic_defun(pic, "read-history", pic_rl_read_history);
+    pic_defun(pic, "write-history", pic_rl_write_history);
+    pic_defun(pic, "truncate-file", pic_rl_truncate_file);
   }
 }