More cmd.exe exploitation.
diff --git a/PCbuild/rt.bat b/PCbuild/rt.bat
index a5b2e5e..8e386c5 100755
--- a/PCbuild/rt.bat
+++ b/PCbuild/rt.bat
@@ -1,40 +1,52 @@
-@rem Run Tests. Run the regression test suite.
-@rem Usage: rt [-d] [-O] [-q] regrtest_args
-@rem -d Run Debug build (python_d.exe). Else release build.
-@rem -O Run python.exe or python_d.exe (see -d) with -O.
-@rem -q "quick" -- normally the tests are run twice, the first time
-@rem after deleting all the .py[co] files reachable from Lib/.
-@rem -q runs the tests just once, and without deleting .py[co] files.
-@rem All leading instances of these switches are shifted off, and
-@rem whatever remains is passed to regrtest.py. For example,
-@rem rt -O -d -x test_thread
-@rem runs
-@rem python_d -O ../lib/test/regrtest.py -x test_thread
-@rem twice, and
-@rem rt -q -g test_binascii
-@rem runs
-@rem python_d ../lib/test/regrtest.py -g test_binascii
-@rem to generate the expected-output file for binascii quickly.
-@setlocal
-@set _exe=python
-@set _qmode=no
-@set _dashO=
-@PATH %PATH%;..\..\tcltk\bin
-@goto CheckOpts
-:Again
-@shift
+@echo off
+rem Run Tests. Run the regression test suite.
+rem Usage: rt [-d] [-O] [-q] regrtest_args
+rem -d Run Debug build (python_d.exe). Else release build.
+rem -O Run python.exe or python_d.exe (see -d) with -O.
+rem -q "quick" -- normally the tests are run twice, the first time
+rem after deleting all the .py[co] files reachable from Lib/.
+rem -q runs the tests just once, and without deleting .py[co] files.
+rem All leading instances of these switches are shifted off, and
+rem whatever remains is passed to regrtest.py. For example,
+rem rt -O -d -x test_thread
+rem runs
+rem python_d -O ../lib/test/regrtest.py -x test_thread
+rem twice, and
+rem rt -q -g test_binascii
+rem runs
+rem python_d ../lib/test/regrtest.py -g test_binascii
+rem to generate the expected-output file for binascii quickly.
+rem
+rem Confusing: if you want to pass a comma-separated list, like
+rem -u network,largefile
+rem then you have to quote it on the rt line, like
+rem rt -u "network,largefile"
+
+setlocal
+
+set exe=python
+set qmode=
+set dashO=
+PATH %PATH%;..\..\tcltk\bin
+
:CheckOpts
-@if "%1"=="-O" set _dashO=-O
-@if "%1"=="-O" goto Again
-@if "%1"=="-q" set _qmode=yes
-@if "%1"=="-q" goto Again
-@if "%1"=="-d" set _exe=python_d
-@if "%1"=="-d" goto Again
-@if "%_qmode%"=="yes" goto Qmode
-@echo Deleting .pyc/.pyo files ...
-@%_exe% rmpyc.py
-%_exe% %_dashO% -E -tt ../lib/test/regrtest.py %1 %2 %3 %4 %5 %6 %7 %8 %9
-@echo About to run again without deleting .pyc/.pyo first:
-@pause
+if "%1"=="-O" (set dashO=-O) & shift & goto CheckOpts
+if "%1"=="-q" (set qmode=yes) & shift & goto CheckOpts
+if "%1"=="-d" (set exe=python_d) & shift & goto CheckOpts
+
+set cmd=%exe% %dashO% -E -tt ../lib/test/regrtest.py %1 %2 %3 %4 %5 %6 %7 %8 %9
+if defined qmode goto Qmode
+
+echo Deleting .pyc/.pyo files ...
+%exe% rmpyc.py
+
+echo on
+%cmd%
+@echo off
+
+echo About to run again without deleting .pyc/.pyo first:
+pause
+
:Qmode
-%_exe% %_dashO% -E -tt ../lib/test/regrtest.py %1 %2 %3 %4 %5 %6 %7 %8 %9
+echo on
+%cmd%