*	Sets the device into blocking or non-blocking mode.
 *
 *----------------------------------------------------------------------
 */

static int
PipeBlockModeProc(
    void *instanceData,		/* Instance data for channel. */
    int mode)			/* TCL_MODE_BLOCKING or
				 * TCL_MODE_NONBLOCKING. */
{
    PipeInfo *infoPtr = (PipeInfo *) instanceData;

    /*
     * Pipes on Windows can not be switched between blocking and nonblocking,

 *	Closes the physical channel.
 *
 *----------------------------------------------------------------------
 */

static int
PipeClose2Proc(
    void *instanceData,		/* Pointer to PipeInfo structure. */
    Tcl_Interp *interp,		/* For error reporting. */
    int flags)			/* Flags that indicate which side to close. */
{
    PipeInfo *pipePtr = (PipeInfo *) instanceData;
    Tcl_Channel errChan;
    int errorCode, result;
    PipeInfo *infoPtr, **nextPtrPtr;

 *	Reads input from the actual channel.
 *
 *----------------------------------------------------------------------
 */

static int
PipeInputProc(
    void *instanceData,		/* Pipe state. */
    char *buf,			/* Where to store data read. */
    int bufSize,		/* How much space is available in the
				 * buffer? */
    int *errorCode)		/* Where to store error code. */
{
    PipeInfo *infoPtr = (PipeInfo *) instanceData;
    WinFile *filePtr = (WinFile*) infoPtr->readFile;

 *	Writes output on the actual channel.
 *
 *----------------------------------------------------------------------
 */

static int
PipeOutputProc(
    void *instanceData,		/* Pipe state. */
    const char *buf,		/* The data buffer. */
    int toWrite,		/* How many bytes to write? */
    int *errorCode)		/* Where to store error code. */
{
    PipeInfo *infoPtr = (PipeInfo *) instanceData;
    WinFile *filePtr = (WinFile*) infoPtr->writeFile;
    DWORD bytesWritten, timeout;

 *	None.
 *
 *----------------------------------------------------------------------
 */

static void
PipeWatchProc(
    void *instanceData,		/* Pipe state. */
    int mask)			/* What events to watch for, OR-ed combination
				 * of TCL_READABLE, TCL_WRITABLE and
				 * TCL_EXCEPTION. */
{
    PipeInfo **nextPtrPtr, *ptr;
    PipeInfo *infoPtr = (PipeInfo *) instanceData;
    int oldMask = infoPtr->watchMask;

 *	None.
 *
 *----------------------------------------------------------------------
 */

static int
PipeGetHandleProc(
    void *instanceData,		/* The pipe state. */
    int direction,		/* TCL_READABLE or TCL_WRITABLE */
    void **handlePtr)		/* Where to store the handle.  */
{
    PipeInfo *infoPtr = (PipeInfo *) instanceData;
    WinFile *filePtr;

    if (direction == TCL_READABLE && infoPtr->readFile) {
	filePtr = (WinFile*) infoPtr->readFile;
	*handlePtr = (void *) filePtr->handle;