1. Add a command line switch to run without the subprocess

2. Remove the shell menu and associated bindings when running
   without the subprocess.
3. Update the IDLE Help and usage text.
4. Update display_port_binding_error to suggest using -n

M PyShell.py
M help.txt

Lib/idlelib/PyShell.py

@@ -332,7 +332,7 @@ def start_subprocess(self):
                 self.rpcclt = rpc.RPCClient(addr)
                 break
             except socket.error, err:
-                print>>sys.__stderr__,"Idle socket error: " + err[1]\
+                print>>sys.__stderr__,"IDLE socket error: " + err[1]\
                                                     + ", retrying..."
         else:
             display_port_binding_error()
@@ -650,7 +650,6 @@ class PyShell(OutputWindow):
     menu_specs = [
         ("file", "_File"),
         ("edit", "_Edit"),
-        ("shell", "_Shell"),
         ("debug", "_Debug"),
         ("options", "_Options"),
         ("windows", "_Windows"),
@@ -661,6 +660,8 @@ class PyShell(OutputWindow):
     from IdleHistory import History
 
     def __init__(self, flist=None):
+        if use_subprocess:
+            self.menu_specs.insert(2, ("shell", "_Shell"))
         self.interp = ModifiedInterpreter(self)
         if flist is None:
             root = Tk()
@@ -686,8 +687,9 @@ def __init__(self, flist=None):
         text.bind("<<toggle-debugger>>", self.toggle_debugger)
         text.bind("<<open-python-shell>>", self.flist.open_shell)
         text.bind("<<toggle-jit-stack-viewer>>", self.toggle_jit_stack_viewer)
-        text.bind("<<view-restart>>", self.view_restart_mark)
-        text.bind("<<restart-shell>>", self.restart_shell)
+        if use_subprocess:
+            text.bind("<<view-restart>>", self.view_restart_mark)
+            text.bind("<<restart-shell>>", self.restart_shell)
         #
         self.save_stdout = sys.stdout
         self.save_stderr = sys.stderr
@@ -810,7 +812,7 @@ def short_title(self):
         return self.shell_title
 
     COPYRIGHT = \
-              'Type "copyright", "credits" or "license" for more information.'
+          'Type "copyright", "credits" or "license()" for more information.'
 
     def begin(self):
         self.resetoutput()
@@ -1072,6 +1074,7 @@ def isatty(self):
        idle  [-ds] [-t title] - [arg]*
 
   -h         print this help message and exit
+  -n         run IDLE without a subprocess (see Help/IDLE Help for details)
 
 The following options will override the IDLE 'settings' configuration:
 
@@ -1120,6 +1123,7 @@ def isatty(self):
 def main():
     global flist, root, use_subprocess
 
+    use_subprocess = True
     enable_shell = False
     enable_edit = False
     debug = False
@@ -1131,7 +1135,7 @@ def main():
     except AttributeError:
         sys.ps1 = '>>> '
     try:
-        opts, args = getopt.getopt(sys.argv[1:], "c:deihr:st:")
+        opts, args = getopt.getopt(sys.argv[1:], "c:deihnr:st:")
     except getopt.error, msg:
         sys.stderr.write("Error: %s\n" % str(msg))
         sys.stderr.write(usage_msg)
@@ -1150,6 +1154,8 @@ def main():
             sys.exit()
         if o == '-i':
             enable_shell = True
+        if o == '-n':
+            use_subprocess = False
         if o == '-r':
             script = a
             if os.path.isfile(script):
@@ -1167,9 +1173,6 @@ def main():
     if args and args[0] == '-':
         cmd = sys.stdin.read()
         enable_shell = True
-
-    use_subprocess = True
-
     # process sys.argv and sys.path:
     for i in range(len(sys.path)):
         sys.path[i] = os.path.abspath(sys.path[i])
@@ -1202,7 +1205,6 @@ def main():
     fixwordbreaks(root)
     root.withdraw()
     flist = PyShellFileList(root)
-
     if enable_edit:
         if not (cmd or script):
             for filename in args:
@@ -1239,19 +1241,19 @@ def main():
 
 def display_port_binding_error():
     print """\
-IDLE cannot run.
+\nIDLE cannot run.
 
-IDLE needs to use a specific TCP/IP port (8833) in order to execute and
-debug programs. IDLE is unable to bind to this port, and so cannot
-start. Here are some possible causes of this problem:
+IDLE needs to use a specific TCP/IP port (8833) in order to communicate with
+its Python execution server.  IDLE is unable to bind to this port, and so
+cannot start. Here are some possible causes of this problem:
 
   1. TCP/IP networking is not installed or not working on this computer
-  2. Another program is running that uses this port
+  2. Another program (another IDLE?) is running that uses this port
   3. Personal firewall software is preventing IDLE from using this port
 
-IDLE makes and accepts connections only with this computer, and does not
-communicate over the internet in any way. Its use of port 8833 should not
-be a security risk on a single-user machine.
+Run IDLE with the -n command line switch to start without a subprocess
+and refer to Help/IDLE Help "Running without a subprocess" for further
+details.
 """
 
 if __name__ == "__main__":

Lib/idlelib/help.txt

@@ -191,3 +191,16 @@ Other preferences:
 Command line usage:
 	
 	Enter idle -h at the command prompt to get a usage message.
+
+Running without a subprocess:
+
+	If IDLE is started with the -n command line switch it will run in a
+	single process and will not create the subprocess which runs the RPC
+	Python execution server.  This can be useful if Python cannot create
+	the subprocess or the RPC socket interface on your platform.  However,
+	in this mode user code is not isolated from IDLE itself.  Also, the
+	environment is not restarted when Run/Run Module (F5) is selected.  If
+	your code has been modified, you must reload() the affected modules and
+	re-import any specific items (e.g. from foo import baz) if the changes
+	are to take effect.  For these reasons, it is preferable to run IDLE
+	with the default subprocess if at all possible.