* ext/tk/tkutil.c (tk_conv_args): forget to revert thread_critical

  and gc_disable when raise ArgumentError.
* ext/tk/lib/remote-tk.rb: RemoteTkIp doesn't need to include TkUtil.
* ext/tcltklib/tcltklib.c: add TclTkIp#has_mainwindow? method.
* ext/tk/lib/tk.rb: add Tk.has_mainwindow? method.
* ext/tk/lib/multi-tk.rb: add MultiTkIp#has_mainwindow? method.
* ext/tk/lib/remote-tk.rb: add RemoteTkIp#has_mainwindow? method.
* ext/tk/lib/multi-tk.rb: slave IP fail to exit itself when $SAFE==4.
* ext/tk/lib/multi-tk.rb: remove constants from MultiTkIp module to
  avoid access from external.
* ext/tk/lib/multi-tk.rb: check_root flag is ignored on slave IPs'
  mainloop.
* ext/tk/lib/multi-tk.rb: hang-up Tk.mainloop called on a slave IP
  with $SAFE==4.
* ext/tk/lib/multi-tk.rb: MultiTkIp#bg_eval_proc doesn't work
  properly.
* ext/tk/lib/multi-tk.rb: add MultiTkIp#set_cb_error(proc) and
  cb_error(exc) to log errors at callbacks on safe slave IPs.
* ext/tk/lib/multi-tk.rb: fail to get an available slave IP object
  when call Tk.mainloop in the block which is given to new_* method,
  because cannot finish initialize while the root widget is alive.
* ext/tk/lib/multi-tk.rb: fail to control a slave IP when Tk.mainloop
  runs on the IP.


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_1_8@8817 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

7 files changed, 183 insertions, 63 deletions

diff --git a/ext/tcltklib/MANUAL.eng b/ext/tcltklib/MANUAL.eng
index 9e7bd20d37..1db61f228e 100644
--- a/ext/tcltklib/MANUAL.eng
+++ b/ext/tcltklib/MANUAL.eng
@@ -310,6 +310,11 @@ class TclTkIp
        : Check whether the interpreter is already deleted.
        : If deleted, returns true. 
 
+    has_mainwindow?
+       : Check whether the interpreter has a MainWindow (root widget).
+       : If has, returns true. If doesn't, returns false.  
+       : If IP is already deleted, returns nil. 
+
     restart
        : Restart Tk part of the interpreter. 
        : Use this when you need Tk functions after destroying the
diff --git a/ext/tcltklib/MANUAL.euc b/ext/tcltklib/MANUAL.euc
index f90dcff3e4..5dd36726ba 100644
--- a/ext/tcltklib/MANUAL.euc
+++ b/ext/tcltklib/MANUAL.euc
@@ -422,6 +422,11 @@ require "tcltklib" すると, 以下のモジュール, クラスが利用可能です.
          : delete 済みでコマンドを受け付けない状態になっているならば
          : true を返す．
 
+      has_mainwindow?
+         : Tcl/Tk インタープリタにメインウィンドウ (root widget) が
+         : 存在すれば true を，存在しなければ false を返す．
+         : インタープリタが既に delete 済みであれば nil を返す．
+
       restart
          : Tcl/Tk インタープリタの Tk 部分の初期化，再起動を行う．
          : 一旦 root widget を破壊した後に再度 Tk の機能が必要と
diff --git a/ext/tcltklib/tcltklib.c b/ext/tcltklib/tcltklib.c
index b088ef7cf7..d1e5f9d0d0 100644
--- a/ext/tcltklib/tcltklib.c
+++ b/ext/tcltklib/tcltklib.c
@@ -4,7 +4,7 @@
  *              Oct. 24, 1997   Y. Matsumoto
  */
 
-#define TCLTKLIB_RELEASE_DATE "2005-07-19"
+#define TCLTKLIB_RELEASE_DATE "2005-07-22"
 
 #include "ruby.h"
 #include "rubysig.h"
@@ -511,6 +511,7 @@ get_ip(self)
     }
     if (ptr->ip == (Tcl_Interp*)NULL) {
         /* rb_raise(rb_eRuntimeError, "deleted IP"); */
+        return((struct tcltkip *)NULL);
     }
     return ptr;
 }
@@ -5293,6 +5294,22 @@ ip_is_deleted_p(self)
     }
 }
 
+static VALUE
+ip_has_mainwindow_p(self)
+    VALUE self;
+{
+    struct tcltkip *ptr = get_ip(self);
+
+    if (ptr == (struct tcltkip *)NULL || ptr->ip == (Tcl_Interp *)NULL 
+        || Tcl_InterpDeleted(ptr->ip)) {
+        return Qnil;
+    } else if (Tk_MainWindow(ptr->ip) == (Tk_Window)NULL) {
+        return Qfalse;
+    } else {
+        return Qtrue;
+    }
+}
+
 
 static VALUE
 #ifdef HAVE_STDARG_PROTOTYPES
@@ -8557,6 +8574,7 @@ Init_tcltklib()
     rb_define_method(ip, "allow_ruby_exit=", ip_allow_ruby_exit_set, 1);
     rb_define_method(ip, "delete", ip_delete, 0);
     rb_define_method(ip, "deleted?", ip_is_deleted_p, 0);
+    rb_define_method(ip, "has_mainwindow?", ip_has_mainwindow_p, 0);
     rb_define_method(ip, "invalid_namespace?", ip_has_invalid_namespace_p, 0);
     rb_define_method(ip, "_eval", ip_eval, 1);
     rb_define_method(ip, "_toUTF8", ip_toUTF8, -1);
diff --git a/ext/tk/lib/multi-tk.rb b/ext/tk/lib/multi-tk.rb
index e8bbf67de1..3119080734 100644
--- a/ext/tk/lib/multi-tk.rb
+++ b/ext/tk/lib/multi-tk.rb
@@ -7,7 +7,7 @@ require 'tkutil'
 require 'thread'
 
 if defined? Tk
-  fail RuntimeError, "'multi-tk' library must be required before requiring 'tk'"
+  fail RuntimeError,"'multi-tk' library must be required before requiring 'tk'"
 end
 
 ################################################
@@ -54,7 +54,7 @@ MultiTkIp_OK.freeze
 ################################################
 # methods for construction
 class MultiTkIp
-  SLAVE_IP_ID = ['slave'.freeze, '0'.taint].freeze
+  @@SLAVE_IP_ID = ['slave'.freeze, '0'.taint].freeze
 
   @@IP_TABLE = {}.taint unless defined?(@@IP_TABLE)
 
@@ -86,9 +86,26 @@ class MultiTkIp
           @ip.cb_eval(@cmd, *args)
         rescue TkCallbackBreak, TkCallbackContinue => e
           fail e
+	rescue SecurityError => e
+          # in 'exit', 'exit!', and 'abort' : security error --> delete IP
+          if e.backtrace[0] =~ /^(.+?):(\d+):in `(exit|exit!|abort)'/
+	    @ip.delete
+          elsif @ip.safe?
+	    if @ip.respond_to?(:cb_error)
+              @ip.cb_error(e)
+            else
+              nil # ignore
+            end
+          else
+            fail e
+          end
         rescue Exception => e
           if @ip.safe?
-            nil # ignore
+	    if @ip.respond_to?(:cb_error)
+              @ip.cb_error(e)
+            else
+              nil # ignore
+            end
           else
             fail e
           end
@@ -161,6 +178,18 @@ class MultiTkIp
 
   ######################################
 
+  def set_cb_error(cmd = Proc.new)
+    @cb_error_proc[0] = cmd
+  end
+
+  def cb_error(e)
+    if @cb_error_proc[0].respond_to?(:call)
+      @cb_error_proc[0].call(e)
+    end
+  end
+
+  ######################################
+
   def set_safe_level(safe)
     if safe > @safe_level[0]
       @safe_level[0] = safe
@@ -192,7 +221,7 @@ class MultiTkIp
   end
 
   def running_mainloop?
-    @wait_on_mainloop[1]
+    @wait_on_mainloop[1] > 0
   end
 
   def _destroy_slaves_of_slaveIP(ip)
@@ -442,13 +471,21 @@ class MultiTkIp
   private :_receiver_eval_proc, :_receiver_eval_proc_core
 
   def _receiver_mainloop(check_root)
-    Thread.new{
-      while !@interp.deleted?
-        inf = @interp._invoke_without_enc('info', 'command', '.')
-        break if !inf.kind_of?(String) || inf != '.'
-        sleep 0.5
-      end
-    }
+    if @evloop_thread[0] && @evloop_thread[0].alive?
+      @evloop_thread[0]
+    else
+      @evloop_thread[0] = Thread.new{
+	while !@interp.deleted?
+	  #if check_root
+	  #  inf = @interp._invoke_without_enc('info', 'command', '.')
+	  #  break if !inf.kind_of?(String) || inf != '.'
+	  #end
+          break if check_root && !@interp.has_mainwindow?
+	  sleep 0.5
+	end
+      }
+      @evloop_thread[0]
+    end
   end
 
   def _create_receiver_and_watchdog(lvl = $SAFE)
@@ -456,7 +493,7 @@ class MultiTkIp
 
     # command-procedures receiver
     receiver = Thread.new(lvl){|safe_level|
-      last_thread = nil
+      last_thread = {}
 
       loop do
         break if @interp.deleted?
@@ -479,8 +516,9 @@ class MultiTkIp
 
         else
           # procedure
-          last_thread = _receiver_eval_proc(last_thread, safe_level, 
-                                            thread, cmd, *args)
+          last_thread[thread] = _receiver_eval_proc(last_thread[thread], 
+						    safe_level, thread, 
+						    cmd, *args)
         end
       end
     }
@@ -539,6 +577,8 @@ class MultiTkIp
 
     @slave_ip_top = {}.taint
 
+    @evloop_thread = [].taint
+
     unless keys.kind_of? Hash
       fail ArgumentError, "expecting a Hash object for the 2nd argument"
     end
@@ -548,7 +588,7 @@ class MultiTkIp
 
     @system = Object.new
 
-    @wait_on_mainloop = [true, false]
+    @wait_on_mainloop = [true, 0].taint
 
     @threadgroup  = Thread.current.group
 
@@ -657,7 +697,7 @@ class MultiTkIp
 
   ######################################
 
-  SAFE_OPT_LIST = [
+  @@SAFE_OPT_LIST = [
     'accessPath'.freeze, 
     'statics'.freeze, 
     'nested'.freeze, 
@@ -676,7 +716,7 @@ class MultiTkIp
         name = v 
       elsif k_str == 'safe'
         safe = v
-      elsif SAFE_OPT_LIST.member?(k_str)
+      elsif @@SAFE_OPT_LIST.member?(k_str)
         safe_opts[k_str] = v
       else
         tk_opts[k_str] = v
@@ -692,8 +732,8 @@ class MultiTkIp
   private :_parse_slaveopts
 
   def _create_slave_ip_name
-    name = SLAVE_IP_ID.join('')
-    SLAVE_IP_ID[1].succ!
+    name = @@SLAVE_IP_ID.join('')
+    @@SLAVE_IP_ID[1].succ!
     name
   end
   private :_create_slave_ip_name
@@ -924,11 +964,15 @@ class MultiTkIp
     @tk_table_list = []
     @slave_ip_tbl = {}
     @slave_ip_top = {}
+    @cb_error_proc = []
+    @evloop_thread = []
 
     @tk_windows.taint unless @tk_windows.tainted?
     @tk_table_list.taint unless @tk_table_list.tainted?
     @slave_ip_tbl.taint unless @slave_ip_tbl.tainted?
     @slave_ip_top.taint unless @slave_ip_top.tainted?
+    @cb_error_proc.taint unless @cb_error_proc.tainted?
+    @evloop_thread.taint unless @evloop_thread.tainted?
 
     name, safe, safe_opts, tk_opts = _parse_slaveopts(keys)
 
@@ -975,7 +1019,8 @@ class MultiTkIp
 
     @system = Object.new
 
-    @wait_on_mainloop = [true, false]
+    @wait_on_mainloop = [true, 0].taint
+    # @wait_on_mainloop = [false, 0].taint
 
     @threadgroup  = ThreadGroup.new
 
@@ -1088,7 +1133,10 @@ class << MultiTkIp
     end
 
     ip = __new(__getip, nil, keys)
-    ip.eval_proc(proc{$SAFE=ip.safe_level; Proc.new}.call) if block_given?
+    #ip.eval_proc(proc{$SAFE=ip.safe_level; Proc.new}.call) if block_given?
+     if block_given?
+       Thread.new{ip.eval_proc(proc{$SAFE=ip.safe_level; Proc.new}.call)}
+     end
     ip
   end
 
@@ -1109,7 +1157,10 @@ class << MultiTkIp
     end
 
     ip = __new(__getip, false, keys)
-    ip.eval_proc(proc{$SAFE=ip.safe_level; Proc.new}.call) if block_given?
+    # ip.eval_proc(proc{$SAFE=ip.safe_level; Proc.new}.call) if block_given?
+    if block_given?
+      Thread.new{ip.eval_proc(proc{$SAFE=ip.safe_level; Proc.new}.call)}
+    end
     ip
   end
   alias new_trusted_slave new_slave
@@ -1127,7 +1178,10 @@ class << MultiTkIp
     end
 
     ip = __new(__getip, true, keys)
-    ip.eval_proc(proc{$SAFE=ip.safe_level; Proc.new}.call) if block_given?
+    # ip.eval_proc(proc{$SAFE=ip.safe_level; Proc.new}.call) if block_given?
+    if block_given?
+      Thread.new{ip.eval_proc(proc{$SAFE=ip.safe_level; Proc.new}.call)}
+    end
     ip
   end
   alias new_safeTk new_safe_slave
@@ -1504,7 +1558,11 @@ class MultiTkIp
       backup_ip = current['callback_ip']
       current['callback_ip'] = self
       begin
-        eval_proc_core(false, cmd, safe_level, *args)
+        eval_proc_core(false, 
+	               proc{|safe, *params|
+		         $SAFE=safe if $SAFE < safe
+                         cmd.call(*params)
+                       }, safe_level, *args)
       ensure
         current['callback_ip'] = backup_ip
       end
@@ -1514,7 +1572,7 @@ class MultiTkIp
                        $SAFE=safe if $SAFE < safe
                        Thread.new(*params, &cmd).value
                      },
-                     *args)
+                     safe_level, *args)
     end
   end
   alias call eval_proc
@@ -1528,15 +1586,19 @@ class MultiTkIp
       end
     end
     Thread.new{
+      eval_proc(cmd, *args)
+=begin
       eval_proc_core(false, 
                      proc{|safe, *params| 
                        $SAFE=safe if $SAFE < safe
                        Thread.new(*params, &cmd).value
                      },
-                     *args)
+                     safe_level, *args)
+=end
     }
   end
   alias background_eval_proc bg_eval_proc
+  alias thread_eval_proc bg_eval_proc
   alias bg_call bg_eval_proc
   alias background_call bg_eval_proc
 
@@ -1550,7 +1612,7 @@ class MultiTkIp
                    proc{|safe| 
                      $SAFE=safe if $SAFE < safe
                      Kernel.eval(cmd, *eval_args)
-                   })
+                   }, safe_level)
   end
   alias eval_str eval_string
 
@@ -1564,7 +1626,7 @@ class MultiTkIp
                      proc{|safe| 
                        $SAFE=safe if $SAFE < safe
                        Kernel.eval(cmd, *eval_args)
-                     })
+                     }, safe_level)
     }
   end
   alias background_eval_string bg_eval_string
@@ -1679,6 +1741,10 @@ class << MultiTkIp
     __getip.deleted?
   end
 
+  def has_mainwindow?
+    __getip.has_mainwindow?
+  end
+
   def invalid_namespace?
     __getip.invalid_namespace?
   end
@@ -1860,22 +1926,24 @@ class MultiTkIp
     if self != @@DEFAULT_MASTER
       if @wait_on_mainloop[0]
         begin
-          @wait_on_mainloop[1] = true
-          @cmd_queue.enq([@system, 'call_mainloop', 
-                           Thread.current, check_root])
-          Thread.stop
+          @wait_on_mainloop[1] += 1
+          if $SAFE >= 4
+	    _receiver_mainloop(check_root).join
+          else
+            @cmd_queue.enq([@system, 'call_mainloop', 
+                            Thread.current, check_root])
+            Thread.stop
+          end
         rescue MultiTkIp_OK => ret
           # return value
-          @wait_on_mainloop[1] = false
           if ret.value.kind_of?(Thread)
             return ret.value.value
           else
             return ret.value
           end
-        rescue SystemExit
+        rescue SystemExit => e
           # exit IP
           warn("Warning: " + $! + " on " + self.inspect) if $DEBUG
-          @wait_on_mainloop[1] = false
           begin
             self._eval_without_enc('exit')
           rescue Exception
@@ -1887,17 +1955,18 @@ class MultiTkIp
                  ((e.message.length > 0)? ' "' + e.message + '"': '') +  
                  " on " + self.inspect) 
           end
-          @wait_on_mainloop[1] = false
           return e
+        rescue Exception => e
+	  return e
         ensure
-          @wait_on_mainloop[1] = false
+          @wait_on_mainloop[1] -= 1
         end
       end
       return
     end
 
     unless restart_on_dead
-      @wait_on_mainloop[1] = true
+      @wait_on_mainloop[1] += 1
 =begin
       begin
         @interp.mainloop(check_root)
@@ -1909,11 +1978,13 @@ class MultiTkIp
         end
       end
 =end
-      @interp.mainloop(check_root)
-      @wait_on_mainloop[1] = false
+      begin
+	@interp.mainloop(check_root)
+      ensure
+	@wait_on_mainloop[1] -= 1
+      end
     else
       loop do
-        @wait_on_mainloop[1] = true
         break unless self.alive?
         if check_root
           begin
@@ -1924,6 +1995,7 @@ class MultiTkIp
         end
         break if @interp.deleted?
         begin
+	  @wait_on_mainloop[1] += 1
           @interp.mainloop(check_root)
         rescue StandardError => e
           if TclTkLib.mainloop_abort_on_exception != nil
@@ -1948,7 +2020,7 @@ class MultiTkIp
 =end
           raise e
         ensure
-          @wait_on_mainloop[1] = false
+          @wait_on_mainloop[1] -= 1
           Thread.pass  # avoid eventloop conflict
         end
       end
@@ -2040,6 +2112,10 @@ class MultiTkIp
     @interp.deleted?
   end
 
+  def has_mainwindow?
+    @interp.has_mainwindow?
+  end
+
   def invalid_namespace?
     @interp.invalid_namespace?
   end
diff --git a/ext/tk/lib/remote-tk.rb b/ext/tk/lib/remote-tk.rb
index ed7f75b336..6e64a1ca2d 100644
--- a/ext/tk/lib/remote-tk.rb
+++ b/ext/tk/lib/remote-tk.rb
@@ -60,8 +60,6 @@ class << RemoteTkIp
 end
 
 class RemoteTkIp
-  include TkUtil
-
   def initialize(remote_ip, displayof=nil, timeout=5)
     if $SAFE >= 4
       fail SecurityError, "cannot access another interpreter at level #{$SAFE}"
@@ -96,7 +94,7 @@ class RemoteTkIp
 
     @safe_level = [$SAFE]
 
-    @wait_on_mainloop = [true, false]
+    @wait_on_mainloop = [true, 0]
 
     @cmd_queue = Queue.new
 
@@ -179,7 +177,7 @@ class RemoteTkIp
       fail SecurityError, "cannot send tainted commands at level #{$SAFE}"
     end
 
-    cmds = @interp._merge_tklist(*_conv_args([], enc_mode, *cmds))
+    cmds = @interp._merge_tklist(*TkUtil::_conv_args([], enc_mode, *cmds))
     if @displayof
       if async
         @interp.__invoke('send', '-async', '-displayof', @displayof, 
@@ -283,6 +281,19 @@ class RemoteTkIp
     end
   end
 
+  def has_mainwindow?
+    begin
+      inf = @interp._invoke_without_enc('info', 'command', '.')
+    rescue Exception
+      return nil
+    end
+    if !inf.kind_of?(String) || inf != '.'
+      false
+    else
+      true
+    end
+  end
+
   def invalid_namespace?
     false
   end
@@ -343,25 +354,25 @@ class RemoteTkIp
 
   def _get_variable(var_name, flag)
     # ignore flag
-    _appsend(false, 'set', _get_eval_string(var_name))
+    _appsend(false, 'set', TkComm::_get_eval_string(var_name))
   end
   def _get_variable2(var_name, index_name, flag)
     # ignore flag
-    _appsend(false, 'set', "#{_get_eval_string(var_name)}(#{_get_eval_string(index_name)})")
+    _appsend(false, 'set', "#{TkComm::_get_eval_string(var_name)}(#{TkComm::_get_eval_string(index_name)})")
   end
 
   def _set_variable(var_name, value, flag)
     # ignore flag
-    _appsend(false, 'set', _get_eval_string(var_name), _get_eval_string(value))
+    _appsend(false, 'set', TkComm::_get_eval_string(var_name), TkComm::_get_eval_string(value))
   end
   def _set_variable2(var_name, index_name, value, flag)
     # ignore flag
-    _appsend(false, 'set', "#{_get_eval_string(var_name)}(#{_get_eval_string(index_name)})", _get_eval_string(value))
+    _appsend(false, 'set', "#{TkComm::_get_eval_string(var_name)}(#{TkComm::_get_eval_string(index_name)})", TkComm::_get_eval_string(value))
   end
 
   def _unset_variable(var_name, flag)
     # ignore flag
-    _appsend(false, 'unset', _get_eval_string(var_name))
+    _appsend(false, 'unset', TkComm::_get_eval_string(var_name))
   end
   def _unset_variable2(var_name, index_name, flag)
     # ignore flag
@@ -369,21 +380,21 @@ class RemoteTkIp
   end
 
   def _get_global_var(var_name)
-    _appsend(false, 'set', _get_eval_string(var_name))
+    _appsend(false, 'set', TkComm::_get_eval_string(var_name))
   end
   def _get_global_var2(var_name, index_name)
-    _appsend(false, 'set', "#{_get_eval_string(var_name)}(#{_get_eval_string(index_name)})")
+    _appsend(false, 'set', "#{TkComm::_get_eval_string(var_name)}(#{TkComm::_get_eval_string(index_name)})")
   end
 
   def _set_global_var(var_name, value)
-    _appsend(false, 'set', _get_eval_string(var_name), _get_eval_string(value))
+    _appsend(false, 'set', TkComm::_get_eval_string(var_name), TkComm::_get_eval_string(value))
   end
   def _set_global_var2(var_name, index_name, value)
-    _appsend(false, 'set', "#{_get_eval_string(var_name)}(#{_get_eval_string(index_name)})", _get_eval_string(value))
+    _appsend(false, 'set', "#{TkComm::_get_eval_string(var_name)}(#{TkComm::_get_eval_string(index_name)})", TkComm::_get_eval_string(value))
   end
 
   def _unset_global_var(var_name)
-    _appsend(false, 'unset', _get_eval_string(var_name))
+    _appsend(false, 'unset', TkComm::_get_eval_string(var_name))
   end
   def _unset_global_var2(var_name, index_name)
     _appsend(false, 'unset', "#{var_name}(#{index_name})")
diff --git a/ext/tk/lib/tk.rb b/ext/tk/lib/tk.rb
index 004e9e8f68..9f6290952e 100644
--- a/ext/tk/lib/tk.rb
+++ b/ext/tk/lib/tk.rb
@@ -1833,6 +1833,10 @@ module Tk
     code
   end
 
+  def Tk.has_mainwindow?
+    INTERP.has_mainwindow?
+  end
+
   def root
     TkRoot.new
   end
@@ -4195,7 +4199,7 @@ end
 #Tk.freeze
 
 module Tk
-  RELEASE_DATE = '2005-07-19'.freeze
+  RELEASE_DATE = '2005-07-22'.freeze
 
   autoload :AUTO_PATH,        'tk/variable'
   autoload :TCL_PACKAGE_PATH, 'tk/variable'
diff --git a/ext/tk/tkutil.c b/ext/tk/tkutil.c
index 464bbafa9c..496649f8c5 100644
--- a/ext/tk/tkutil.c
+++ b/ext/tk/tkutil.c
@@ -8,7 +8,7 @@
 
 ************************************************/
 
-#define TKUTIL_RELEASE_DATE "2005-07-05"
+#define TKUTIL_RELEASE_DATE "2005-07-22"
 
 #include "ruby.h"
 #include "rubysig.h"
@@ -892,14 +892,14 @@ tk_conv_args(argc, argv, self)
     int thr_crit_bup;
     VALUE old_gc;
 
+    if (argc < 2) {
+      rb_raise(rb_eArgError, "too few arguments");
+    }
+
     thr_crit_bup = rb_thread_critical;
     rb_thread_critical = Qtrue;
-
     old_gc = rb_gc_disable();
 
-    if (argc < 2) {
-      rb_raise(rb_eArgError, "too few arguments");
-    }
     for(size = 0, idx = 2; idx < argc; idx++) {
         if (TYPE(argv[idx]) == T_HASH) {
             size += 2 * RHASH(argv[idx])->tbl->num_entries;
@@ -1605,6 +1605,7 @@ Init_tkutil()
                                tk_get_eval_string, -1);
     rb_define_singleton_method(mTK, "_get_eval_enc_str", 
                                tk_get_eval_enc_str, 1);
+    rb_define_singleton_method(mTK, "_conv_args", tk_conv_args, -1);
 
     rb_define_singleton_method(mTK, "bool", tcl2rb_bool, 1);
     rb_define_singleton_method(mTK, "number", tcl2rb_number, 1);