Index: tools.gpr
==================================================================
--- tools.gpr
+++ tools.gpr
@@ -2,11 +2,11 @@
 
 project Tools is
    for Source_Dirs use ("tools");
    for Main use
      ("generate_static_hash_map", "hmac-md5", "hmac-sha1", "hmac-sha256",
-      "sxcat");
+      "sxcat", "timekey");
 
    for Object_Dir use Natools'Object_Dir;
    for Exec_Dir use Natools'Exec_Dir;
 
    package Compiler is

ADDED   tools/timekey.adb
Index: tools/timekey.adb
==================================================================
--- tools/timekey.adb
+++ tools/timekey.adb
@@ -0,0 +1,104 @@
+------------------------------------------------------------------------------
+-- Copyright (c) 2015, Natacha Porté                                        --
+--                                                                          --
+-- Permission to use, copy, modify, and distribute this software for any    --
+-- purpose with or without fee is hereby granted, provided that the above   --
+-- copyright notice and this permission notice appear in all copies.        --
+--                                                                          --
+-- THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES --
+-- WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF         --
+-- MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR  --
+-- ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES   --
+-- WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN    --
+-- ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF  --
+-- OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.           --
+------------------------------------------------------------------------------
+
+with Ada.Calendar;
+with Ada.Command_Line;
+with Ada.Text_IO;
+with Natools.Time_IO.RFC_3339;
+with Natools.Time_Keys;
+
+procedure Timekey is
+   procedure Process (Line : in String);
+      --  Guess the type of Line and convert it to or from type.
+
+   procedure Process_Input;
+      --  Read lines from current input and process them.
+
+
+   Input_Processed : Boolean := False;
+   Empty : Boolean := True;
+   Verbose : Boolean := False;
+
+
+   procedure Process (Line : in String) is
+   begin
+      if Verbose then
+         Ada.Text_IO.Put (Line);
+      end if;
+
+      if Natools.Time_Keys.Is_Valid (Line) then
+         if Verbose then
+            Ada.Text_IO.Put (" => ");
+         end if;
+
+         Ada.Text_IO.Put_Line
+           (Natools.Time_IO.RFC_3339.Image
+              (Natools.Time_Keys.To_Time (Line), Duration'Aft, False));
+
+      elsif Natools.Time_IO.RFC_3339.Is_Valid (Line) then
+         if Verbose then
+            Ada.Text_IO.Put (" => ");
+         end if;
+
+         Ada.Text_IO.Put_Line
+           (Natools.Time_Keys.To_Key (Natools.Time_IO.RFC_3339.Value (Line)));
+      end if;
+   end Process;
+
+
+   procedure Process_Input is
+   begin
+      if Input_Processed then
+         return;
+      else
+         Input_Processed := True;
+      end if;
+
+      begin
+         loop
+            Process (Ada.Text_IO.Get_Line);
+         end loop;
+      exception
+         when Ada.Text_IO.End_Error => null;
+      end;
+   end Process_Input;
+begin
+   for I in 1 .. Ada.Command_Line.Argument_Count loop
+      if Ada.Command_Line.Argument (I) = "-" then
+         Empty := False;
+         Process_Input;
+      elsif Ada.Command_Line.Argument (I) = "-v" then
+         Verbose := True;
+      else
+         Empty := False;
+         Process (Ada.Command_Line.Argument (I));
+      end if;
+   end loop;
+
+   if Empty then
+      declare
+         Now : constant Ada.Calendar.Time := Ada.Calendar.Clock;
+      begin
+         if Verbose then
+            Ada.Text_IO.Put
+              (Natools.Time_IO.RFC_3339.Image (Now, Duration'Aft, False)
+               & " => ");
+         end if;
+
+         Ada.Text_IO.Put_Line (Natools.Time_Keys.To_Key (Now));
+      end;
+   end if;
+end Timekey;