Merged changes from scriptics-tclpro-1-3-b2 branch

1 files changed, 25 insertions, 5 deletions

diff --git a/win/tclWinChan.c b/win/tclWinChan.c
index e2126fb..4052e87 100644
--- a/win/tclWinChan.c
+++ b/win/tclWinChan.c
@@ -9,7 +9,7 @@
  * See the file "license.terms" for information on usage and redistribution
  * of this file, and for a DISCLAIMER OF ALL WARRANTIES.
  *
- * RCS: @(#) $Id: tclWinChan.c,v 1.6 1999/04/16 00:48:07 stanton Exp $
+ * RCS: @(#) $Id: tclWinChan.c,v 1.7 1999/05/22 01:20:15 stanton Exp $
  */
 
 #include "tclWinInt.h"
@@ -811,13 +811,23 @@ TclpOpenFileChannel(interp, fileName, modeString, permissions)
 	}
 	channel = TclpCreateCommandChannel(readFile, writeFile, NULL, 0, NULL);
 	break;
-    case FILE_TYPE_CHAR:
-    default:
+    case FILE_TYPE_DISK:
 	channel = TclWinOpenFileChannel(handle, channelName,
 					channelPermissions,
 					(mode & O_APPEND) ? FILE_APPEND : 0);
 	break;
 
+    case FILE_TYPE_UNKNOWN:
+    case FILE_TYPE_CHAR:
+    default:
+	/*
+	 * The handle is of an unknown type, probably /dev/nul equivalent
+	 * or possibly a closed handle.  Don't use it, otherwise Tk runs into
+	 * trouble with the MS DevStudio debugger.
+	 */
+	
+	channel = NULL;
+	break;
     }
 
     Tcl_DStringFree(&buffer);
@@ -915,11 +925,21 @@ Tcl_MakeFileChannel(rawHandle, mode)
 	}
 	channel = TclpCreateCommandChannel(readFile, writeFile, NULL, 0, NULL);
 	break;
-    case FILE_TYPE_UNKNOWN:
+
+    case FILE_TYPE_DISK:
+	channel = TclWinOpenFileChannel(handle, channelName, mode, 0);
 	break;
+	
+    case FILE_TYPE_UNKNOWN:
     case FILE_TYPE_CHAR:
     default:
-	channel = TclWinOpenFileChannel(handle, channelName, mode, 0);
+	/*
+	 * The handle is of an unknown type, probably /dev/nul equivalent
+	 * or possibly a closed handle.  Don't use it, otherwise Tk runs into
+	 * trouble with the MS DevStudio debugger.
+	 */
+	
+	channel = NULL;
 	break;
 
     }