From 058c128660f07f5e5a13e99dcbec3ff6f738a1a7 Mon Sep 17 00:00:00 2001
From: davidg <davidg>
Date: Tue, 18 Jul 2000 02:16:31 +0000
Subject: Win2K OS bug with GetStdHandle(STD_OUTPUT_HANDLE) returning
 0x00010001 instead of INVALID_HANDLE_VALUE for WinMain apps. Added a new test
 case to catch it.

---
 win/tclWinChan.c | 24 +++++++++++++++++++-----
 1 file changed, 19 insertions(+), 5 deletions(-)

diff --git a/win/tclWinChan.c b/win/tclWinChan.c
index 70bf804..f40d361 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 1.10 2000/04/20 01:30:20 hobbs Exp $
+ * RCS: @(#) $Id: tclWinChan.c,v 1.11 2000/07/18 02:16:31 davidg Exp $
  */
 
 #include "tclWinInt.h"
@@ -970,6 +970,9 @@ TclpGetDefaultStdChannel(type)
     int mode;
     char *bufMode;
     DWORD handleId;		/* Standard handle to retrieve. */
+    char dummyBuff[1];		/* Buffer for the WriteFile test */
+    DWORD dummyWritten;		/* Required parameter for WriteFile */
+
 
     switch (type) {
 	case TCL_STDIN:
@@ -999,15 +1002,26 @@ TclpGetDefaultStdChannel(type)
      * is not a console mode application, even though this is not a valid
      * handle.
      */
-    
+
     if ((handle == INVALID_HANDLE_VALUE) || (handle == 0)) {
-	return NULL;
+	return (Tcl_Channel) NULL;
     }
-    
+
+    /*
+     * Win2K BUG: GetStdHandle(STD_OUTPUT_HANDLE) can return what appears
+     * to be a valid handle.  Do an extra test with WriteFile() "touching"
+     * the handle.
+     */
+
+    if ((type == TCL_STDOUT)
+	    && !WriteFile(handle, dummyBuff, 0, &dummyWritten, NULL)) {
+	return (Tcl_Channel) NULL;
+    }
+
     channel = Tcl_MakeFileChannel(handle, mode);
 
     if (channel == NULL) {
-	return NULL;
+	return (Tcl_Channel) NULL;
     }
 
     /*
-- 
cgit v0.12