[NTVDM]

[reactos.git] / subsystems / ntvdm / dos.c

diff --git a/subsystems/ntvdm/dos.c b/subsystems/ntvdm/dos.c
index 8faff7c..8eb71e3 100644 (file)
--- a/subsystems/ntvdm/dos.c
+++ b/subsystems/ntvdm/dos.c
@@ -29,6 +29,30 @@ static BOOLEAN DosUmbLinked = FALSE;
 
 /* PRIVATE FUNCTIONS **********************************************************/
 
+/* Taken from base/shell/cmd/console.c */
+static BOOL IsConsoleHandle(HANDLE hHandle)
+{
+    DWORD dwMode;
+
+    /* Check whether the handle may be that of a console... */
+    if ((GetFileType(hHandle) & FILE_TYPE_CHAR) == 0) return FALSE;
+
+    /*
+     * It may be. Perform another test... The idea comes from the
+     * MSDN description of the WriteConsole API:
+     *
+     * "WriteConsole fails if it is used with a standard handle
+     *  that is redirected to a file. If an application processes
+     *  multilingual output that can be redirected, determine whether
+     *  the output handle is a console handle (one method is to call
+     *  the GetConsoleMode function and check whether it succeeds).
+     *  If the handle is a console handle, call WriteConsole. If the
+     *  handle is not a console handle, the output is redirected and
+     *  you should call WriteFile to perform the I/O."
+     */
+    return GetConsoleMode(hHandle, &dwMode);
+}
+
 static VOID DosCombineFreeBlocks(WORD StartBlock)
 {
     PDOS_MCB CurrentMcb = SEGMENT_TO_MCB(StartBlock), NextMcb;