Initial revision

1 files changed, 2470 insertions, 0 deletions

diff --git a/win/tclWinPipe.c b/win/tclWinPipe.c
new file mode 100644
index 0000000..a7aeaf4
--- /dev/null
+++ b/win/tclWinPipe.c
@@ -0,0 +1,2470 @@
+/* 
+ * tclWinPipe.c --
+ *
+ *	This file implements the Windows-specific exec pipeline functions,
+ *	the "pipe" channel driver, and the "pid" Tcl command.
+ *
+ * Copyright (c) 1996-1997 by Sun Microsystems, Inc.
+ *
+ * See the file "license.terms" for information on usage and redistribution
+ * of this file, and for a DISCLAIMER OF ALL WARRANTIES.
+ *
+ * SCCS: @(#) tclWinPipe.c 1.49 97/11/06 17:33:03
+ */
+
+#include "tclWinInt.h"
+
+#include <dos.h>
+#include <fcntl.h>
+#include <io.h>
+#include <sys/stat.h>
+
+/*
+ * The following variable is used to tell whether this module has been
+ * initialized.
+ */
+
+static int initialized = 0;
+
+/*
+ * The following defines identify the various types of applications that 
+ * run under windows.  There is special case code for the various types.
+ */
+
+#define APPL_NONE	0
+#define APPL_DOS	1
+#define APPL_WIN3X	2
+#define APPL_WIN32	3
+
+/*
+ * The following constants and structures are used to encapsulate the state
+ * of various types of files used in a pipeline.
+ */
+
+#define WIN32S_PIPE 1		/* Win32s emulated pipe. */
+#define WIN32S_TMPFILE 2	/* Win32s emulated temporary file. */
+#define WIN_FILE 3		/* Basic Win32 file. */
+
+/*
+ * This structure encapsulates the common state associated with all file
+ * types used in a pipeline.
+ */
+
+typedef struct WinFile {
+    int type;			/* One of the file types defined above. */
+    HANDLE handle;		/* Open file handle. */
+} WinFile;
+
+/*
+ * The following structure is used to keep track of temporary files under
+ * Win32s and delete the disk file when the open handle is closed.
+ * The type field will be WIN32S_TMPFILE.
+ */
+
+typedef struct TmpFile {
+    WinFile file;		/* Common part. */
+    char name[MAX_PATH];	/* Name of temp file. */
+} TmpFile;
+
+/*
+ * The following structure represents a synchronous pipe under Win32s.
+ * The type field will be WIN32S_PIPE.  The handle field will refer to
+ * an open file when Tcl is reading from the "pipe", otherwise it is
+ * INVALID_HANDLE_VALUE.
+ */
+
+typedef struct WinPipe {
+    WinFile file;		/* Common part. */
+    struct WinPipe *otherPtr;	/* Pointer to the WinPipe structure that
+				 * corresponds to the other end of this 
+				 * pipe. */
+    char *fileName;		/* The name of the staging file that gets 
+				 * the data written to this pipe.  Malloc'd.
+				 * and shared by both ends of the pipe.  Only
+				 * when both ends are freed will fileName be
+				 * freed and the file it refers to deleted. */
+} WinPipe;
+
+/*
+ * This list is used to map from pids to process handles.
+ */
+
+typedef struct ProcInfo {
+    HANDLE hProcess;
+    DWORD dwProcessId;
+    struct ProcInfo *nextPtr;
+} ProcInfo;
+
+static ProcInfo *procList;
+
+/*
+ * State flags used in the PipeInfo structure below.
+ */
+
+#define PIPE_PENDING	(1<<0)	/* Message is pending in the queue. */
+#define PIPE_ASYNC	(1<<1)	/* Channel is non-blocking. */
+
+/*
+ * This structure describes per-instance data for a pipe based channel.
+ */
+
+typedef struct PipeInfo {
+    Tcl_Channel channel;	/* Pointer to channel structure. */
+    int validMask;		/* OR'ed combination of TCL_READABLE,
+				 * TCL_WRITABLE, or TCL_EXCEPTION: indicates
+				 * which operations are valid on the file. */
+    int watchMask;		/* OR'ed combination of TCL_READABLE,
+				 * TCL_WRITABLE, or TCL_EXCEPTION: indicates
+				 * which events should be reported. */
+    int flags;			/* State flags, see above for a list. */
+    TclFile readFile;		/* Output from pipe. */
+    TclFile writeFile;		/* Input from pipe. */
+    TclFile errorFile;		/* Error output from pipe. */
+    int numPids;		/* Number of processes attached to pipe. */
+    Tcl_Pid *pidPtr;		/* Pids of attached processes. */
+    struct PipeInfo *nextPtr;	/* Pointer to next registered pipe. */
+} PipeInfo;
+
+/*
+ * The following pointer refers to the head of the list of pipes
+ * that are being watched for file events.
+ */
+
+static PipeInfo *firstPipePtr;
+
+/*
+ * The following structure is what is added to the Tcl event queue when
+ * pipe events are generated.
+ */
+
+typedef struct PipeEvent {
+    Tcl_Event header;		/* Information that is standard for
+				 * all events. */
+    PipeInfo *infoPtr;		/* Pointer to pipe info structure.  Note
+				 * that we still have to verify that the
+				 * pipe exists before dereferencing this
+				 * pointer. */
+} PipeEvent;
+
+/*
+ * Declarations for functions used only in this file.
+ */
+
+static int	ApplicationType(Tcl_Interp *interp, const char *fileName,
+		    char *fullName);
+static void	BuildCommandLine(int argc, char **argv, Tcl_DString *linePtr);
+static void	CopyChannel(HANDLE dst, HANDLE src);
+static BOOL	HasConsole(void);
+static TclFile	MakeFile(HANDLE handle);
+static char *	MakeTempFile(Tcl_DString *namePtr);
+static int	PipeBlockModeProc(ClientData instanceData, int mode);
+static void	PipeCheckProc _ANSI_ARGS_((ClientData clientData,
+		    int flags));
+static int	PipeCloseProc(ClientData instanceData, Tcl_Interp *interp);
+static int	PipeEventProc(Tcl_Event *evPtr, int flags);
+static void	PipeExitHandler(ClientData clientData);
+static int	PipeGetHandleProc(ClientData instanceData, int direction,
+		    ClientData *handlePtr);
+static void	PipeInit(void);
+static int	PipeInputProc(ClientData instanceData, char *buf, int toRead,
+		    int *errorCode);
+static int	PipeOutputProc(ClientData instanceData, char *buf, int toWrite,
+		    int *errorCode);
+static void	PipeWatchProc(ClientData instanceData, int mask);
+static void	PipeSetupProc _ANSI_ARGS_((ClientData clientData,
+		    int flags));
+static int	TempFileName(char name[MAX_PATH]);
+
+/*
+ * This structure describes the channel type structure for command pipe
+ * based IO.
+ */
+
+static Tcl_ChannelType pipeChannelType = {
+    "pipe",			/* Type name. */
+    PipeBlockModeProc,		/* Set blocking or non-blocking mode.*/
+    PipeCloseProc,		/* Close proc. */
+    PipeInputProc,		/* Input proc. */
+    PipeOutputProc,		/* Output proc. */
+    NULL,			/* Seek proc. */
+    NULL,			/* Set option proc. */
+    NULL,			/* Get option proc. */
+    PipeWatchProc,		/* Set up notifier to watch the channel. */
+    PipeGetHandleProc,		/* Get an OS handle from channel. */
+};
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * PipeInit --
+ *
+ *	This function initializes the static variables for this file.
+ *
+ * Results:
+ *	None.
+ *
+ * Side effects:
+ *	Creates a new event source.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static void
+PipeInit()
+{
+    initialized = 1;
+    firstPipePtr = NULL;
+    procList = NULL;
+    Tcl_CreateEventSource(PipeSetupProc, PipeCheckProc, NULL);
+    Tcl_CreateExitHandler(PipeExitHandler, NULL);
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * PipeExitHandler --
+ *
+ *	This function is called to cleanup the pipe module before
+ *	Tcl is unloaded.
+ *
+ * Results:
+ *	None.
+ *
+ * Side effects:
+ *	Removes the pipe event source.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static void
+PipeExitHandler(clientData)
+    ClientData clientData;	/* Old window proc */
+{
+    Tcl_DeleteEventSource(PipeSetupProc, PipeCheckProc, NULL);
+    initialized = 0;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * PipeSetupProc --
+ *
+ *	This procedure is invoked before Tcl_DoOneEvent blocks waiting
+ *	for an event.
+ *
+ * Results:
+ *	None.
+ *
+ * Side effects:
+ *	Adjusts the block time if needed.
+ *
+ *----------------------------------------------------------------------
+ */
+
+void
+PipeSetupProc(data, flags)
+    ClientData data;		/* Not used. */
+    int flags;			/* Event flags as passed to Tcl_DoOneEvent. */
+{
+    PipeInfo *infoPtr;
+    Tcl_Time blockTime = { 0, 0 };
+
+    if (!(flags & TCL_FILE_EVENTS)) {
+	return;
+    }
+    
+    /*
+     * Check to see if there is a watched pipe.  If so, poll.
+     */
+
+    for (infoPtr = firstPipePtr; infoPtr != NULL; infoPtr = infoPtr->nextPtr) {
+	if (infoPtr->watchMask) {
+	    Tcl_SetMaxBlockTime(&blockTime);
+	    break;
+	}
+    }
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * PipeCheckProc --
+ *
+ *	This procedure is called by Tcl_DoOneEvent to check the pipe
+ *	event source for events. 
+ *
+ * Results:
+ *	None.
+ *
+ * Side effects:
+ *	May queue an event.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static void
+PipeCheckProc(data, flags)
+    ClientData data;		/* Not used. */
+    int flags;			/* Event flags as passed to Tcl_DoOneEvent. */
+{
+    PipeInfo *infoPtr;
+    PipeEvent *evPtr;
+
+    if (!(flags & TCL_FILE_EVENTS)) {
+	return;
+    }
+    
+    /*
+     * Queue events for any watched pipes that don't already have events
+     * queued.
+     */
+
+    for (infoPtr = firstPipePtr; infoPtr != NULL; infoPtr = infoPtr->nextPtr) {
+	if (infoPtr->watchMask && !(infoPtr->flags & PIPE_PENDING)) {
+	    infoPtr->flags |= PIPE_PENDING;
+	    evPtr = (PipeEvent *) ckalloc(sizeof(PipeEvent));
+	    evPtr->header.proc = PipeEventProc;
+	    evPtr->infoPtr = infoPtr;
+	    Tcl_QueueEvent((Tcl_Event *) evPtr, TCL_QUEUE_TAIL);
+	}
+    }
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * MakeFile --
+ *
+ *	This function constructs a new TclFile from a given data and
+ *	type value.
+ *
+ * Results:
+ *	Returns a newly allocated WinFile as a TclFile.
+ *
+ * Side effects:
+ *	None.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static TclFile
+MakeFile(handle)
+    HANDLE handle;		/* Type-specific data. */
+{
+    WinFile *filePtr;
+
+    filePtr = (WinFile *) ckalloc(sizeof(WinFile));
+    filePtr->type = WIN_FILE;
+    filePtr->handle = handle;
+
+    return (TclFile)filePtr;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclpMakeFile --
+ *
+ *	Make a TclFile from a channel.
+ *
+ * Results:
+ *	Returns a new TclFile or NULL on failure.
+ *
+ * Side effects:
+ *	None.
+ *
+ *----------------------------------------------------------------------
+ */
+
+TclFile
+TclpMakeFile(channel, direction)
+    Tcl_Channel channel;	/* Channel to get file from. */
+    int direction;		/* Either TCL_READABLE or TCL_WRITABLE. */
+{
+    HANDLE handle;
+
+    if (Tcl_GetChannelHandle(channel, direction, 
+	    (ClientData *) &handle) == TCL_OK) {
+	return MakeFile(handle);
+    } else {
+	return (TclFile) NULL;
+    }
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TempFileName --
+ *
+ *	Gets a temporary file name and deals with the fact that the
+ *	temporary file path provided by Windows may not actually exist
+ *	if the TMP or TEMP environment variables refer to a 
+ *	non-existent directory.
+ *
+ * Results:    
+ *	0 if error, non-zero otherwise.  If non-zero is returned, the
+ *	name buffer will be filled with a name that can be used to 
+ *	construct a temporary file.
+ *
+ * Side effects:
+ *	None.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static int
+TempFileName(name)
+    char name[MAX_PATH];	/* Buffer in which name for temporary 
+				 * file gets stored. */
+{
+    if ((GetTempPath(MAX_PATH, name) == 0) ||
+	    (GetTempFileName(name, "TCL", 0, name) == 0)) {
+	name[0] = '.';
+	name[1] = '\0';
+	if (GetTempFileName(name, "TCL", 0, name) == 0) {
+	    return 0;
+	}
+    }
+    return 1;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclpCreateTempFile --
+ *
+ *	This function opens a unique file with the property that it
+ *	will be deleted when its file handle is closed.  The temporary
+ *	file is created in the system temporary directory.
+ *
+ * Results:
+ *	Returns a valid TclFile, or NULL on failure.
+ *
+ * Side effects:
+ *	Creates a new temporary file.
+ *
+ *----------------------------------------------------------------------
+ */
+
+TclFile
+TclpCreateTempFile(contents, namePtr)
+    char *contents;		/* String to write into temp file, or NULL. */
+    Tcl_DString *namePtr;	/* If non-NULL, pointer to initialized 
+				 * DString that is filled with the name of 
+				 * the temp file that was created. */
+{
+    char name[MAX_PATH];
+    HANDLE handle;
+
+    if (TempFileName(name) == 0) {
+	return NULL;
+    }
+
+    handle = CreateFile(name, GENERIC_READ | GENERIC_WRITE, 0, NULL,
+	    CREATE_ALWAYS, FILE_ATTRIBUTE_TEMPORARY|FILE_FLAG_DELETE_ON_CLOSE,
+	    NULL);
+    if (handle == INVALID_HANDLE_VALUE) {
+	goto error;
+    }
+
+    /*
+     * Write the file out, doing line translations on the way.
+     */
+
+    if (contents != NULL) {
+	DWORD result, length;
+	char *p;
+	
+	for (p = contents; *p != '\0'; p++) {
+	    if (*p == '\n') {
+		length = p - contents;
+		if (length > 0) {
+		    if (!WriteFile(handle, contents, length, &result, NULL)) {
+			goto error;
+		    }
+		}
+		if (!WriteFile(handle, "\r\n", 2, &result, NULL)) {
+		    goto error;
+		}
+		contents = p+1;
+	    }
+	}
+	length = p - contents;
+	if (length > 0) {
+	    if (!WriteFile(handle, contents, length, &result, NULL)) {
+		goto error;
+	    }
+	}
+    }
+
+    if (SetFilePointer(handle, 0, NULL, FILE_BEGIN) == 0xFFFFFFFF) {
+	goto error;
+    }
+
+    if (namePtr != NULL) {
+        Tcl_DStringAppend(namePtr, name, -1);
+    }
+
+    /*
+     * Under Win32s a file created with FILE_FLAG_DELETE_ON_CLOSE won't
+     * actually be deleted when it is closed, so we have to do it ourselves.
+     */
+
+    if (TclWinGetPlatformId() == VER_PLATFORM_WIN32s) {
+	TmpFile *tmpFilePtr = (TmpFile *) ckalloc(sizeof(TmpFile));
+	tmpFilePtr->file.type = WIN32S_TMPFILE;
+	tmpFilePtr->file.handle = handle;
+	strcpy(tmpFilePtr->name, name);
+	return (TclFile)tmpFilePtr;
+    } else {
+	return MakeFile(handle);
+    }
+
+  error:
+    TclWinConvertError(GetLastError());
+    CloseHandle(handle);
+    DeleteFile(name);
+    return NULL;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclpOpenFile --
+ *
+ *	This function opens files for use in a pipeline.
+ *
+ * Results:
+ *	Returns a newly allocated TclFile structure containing the
+ *	file handle.
+ *
+ * Side effects:
+ *	None.
+ *
+ *----------------------------------------------------------------------
+ */
+
+TclFile
+TclpOpenFile(path, mode)
+    char *path;
+    int mode;
+{
+    HANDLE handle;
+    DWORD accessMode, createMode, shareMode, flags;
+    SECURITY_ATTRIBUTES sec;
+
+    /*
+     * Map the access bits to the NT access mode.
+     */
+
+    switch (mode & (O_RDONLY | O_WRONLY | O_RDWR)) {
+	case O_RDONLY:
+	    accessMode = GENERIC_READ;
+	    break;
+	case O_WRONLY:
+	    accessMode = GENERIC_WRITE;
+	    break;
+	case O_RDWR:
+	    accessMode = (GENERIC_READ | GENERIC_WRITE);
+	    break;
+	default:
+	    TclWinConvertError(ERROR_INVALID_FUNCTION);
+	    return NULL;
+    }
+
+    /*
+     * Map the creation flags to the NT create mode.
+     */
+
+    switch (mode & (O_CREAT | O_EXCL | O_TRUNC)) {
+	case (O_CREAT | O_EXCL):
+	case (O_CREAT | O_EXCL | O_TRUNC):
+	    createMode = CREATE_NEW;
+	    break;
+	case (O_CREAT | O_TRUNC):
+	    createMode = CREATE_ALWAYS;
+	    break;
+	case O_CREAT:
+	    createMode = OPEN_ALWAYS;
+	    break;
+	case O_TRUNC:
+	case (O_TRUNC | O_EXCL):
+	    createMode = TRUNCATE_EXISTING;
+	    break;
+	default:
+	    createMode = OPEN_EXISTING;
+	    break;
+    }
+
+    /*
+     * If the file is not being created, use the existing file attributes.
+     */
+
+    flags = 0;
+    if (!(mode & O_CREAT)) {
+	flags = GetFileAttributes(path);
+	if (flags == 0xFFFFFFFF) {
+	    flags = 0;
+	}
+    }
+
+    /*
+     * Set up the security attributes so this file is not inherited by
+     * child processes.
+     */
+
+    sec.nLength = sizeof(sec);
+    sec.lpSecurityDescriptor = NULL;
+    sec.bInheritHandle = 0;
+
+    /*
+     * Set up the file sharing mode.  We want to allow simultaneous access.
+     */
+
+    shareMode = FILE_SHARE_READ | FILE_SHARE_WRITE;
+
+    /*
+     * Now we get to create the file.
+     */
+
+    handle = CreateFile(path, accessMode, shareMode, &sec, createMode, flags,
+            (HANDLE) NULL);
+    if (handle == INVALID_HANDLE_VALUE) {
+	DWORD err = GetLastError();
+	if ((err & 0xffffL) == ERROR_OPEN_FAILED) {
+	    err = (mode & O_CREAT) ? ERROR_FILE_EXISTS : ERROR_FILE_NOT_FOUND;
+	}
+        TclWinConvertError(err);
+        return NULL;
+    }
+
+    /*
+     * Seek to the end of file if we are writing.
+     */
+
+    if (mode & O_WRONLY) {
+	SetFilePointer(handle, 0, NULL, FILE_END);
+    }
+
+    return MakeFile(handle);
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclpCreatePipe --
+ *
+ *      Creates an anonymous pipe.  Under Win32s, creates a temp file
+ *	that is used to simulate a pipe.
+ *
+ * Results:
+ *      Returns 1 on success, 0 on failure. 
+ *
+ * Side effects:
+ *      Creates a pipe.
+ *
+ *----------------------------------------------------------------------
+ */
+
+int
+TclpCreatePipe(readPipe, writePipe)
+    TclFile *readPipe;	/* Location to store file handle for
+				 * read side of pipe. */
+    TclFile *writePipe;	/* Location to store file handle for
+				 * write side of pipe. */
+{
+    HANDLE readHandle, writeHandle;
+
+    if (CreatePipe(&readHandle, &writeHandle, NULL, 0) != 0) {
+	*readPipe = MakeFile(readHandle);
+	*writePipe = MakeFile(writeHandle);
+	return 1;
+    }
+
+    if (TclWinGetPlatformId() == VER_PLATFORM_WIN32s) {
+	WinPipe *readPipePtr, *writePipePtr;
+	char buf[MAX_PATH];
+
+	if (TempFileName(buf) != 0) {
+	    readPipePtr = (WinPipe *) ckalloc(sizeof(WinPipe));
+	    writePipePtr = (WinPipe *) ckalloc(sizeof(WinPipe));
+
+	    readPipePtr->file.type = WIN32S_PIPE;
+	    readPipePtr->otherPtr = writePipePtr;
+	    readPipePtr->fileName = strcpy(ckalloc(strlen(buf) + 1), buf);
+	    readPipePtr->file.handle = INVALID_HANDLE_VALUE;
+	    writePipePtr->file.type = WIN32S_PIPE;
+	    writePipePtr->otherPtr = readPipePtr;
+	    writePipePtr->fileName = readPipePtr->fileName;
+	    writePipePtr->file.handle = INVALID_HANDLE_VALUE;
+
+	    *readPipe = (TclFile)readPipePtr;
+	    *writePipe = (TclFile)writePipePtr;
+
+	    return 1;
+	}
+    }
+
+    TclWinConvertError(GetLastError());
+    return 0;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclpCloseFile --
+ *
+ *	Closes a pipeline file handle.  These handles are created by
+ *	TclpOpenFile, TclpCreatePipe, or TclpMakeFile.
+ *
+ * Results:
+ *	0 on success, -1 on failure.
+ *
+ * Side effects:
+ *	The file is closed and deallocated.
+ *
+ *----------------------------------------------------------------------
+ */
+
+int
+TclpCloseFile(file)
+    TclFile file;	/* The file to close. */
+{
+    WinFile *filePtr = (WinFile *) file;
+    WinPipe *pipePtr;
+
+    switch (filePtr->type) {
+	case WIN_FILE:
+	case WIN32S_TMPFILE:
+	    if (CloseHandle(filePtr->handle) == FALSE) {
+		TclWinConvertError(GetLastError());
+		ckfree((char *) filePtr);
+		return -1;
+	    }
+	    /*
+	     * Simulate deleting the file on close for Win32s.
+	     */
+
+	    if (filePtr->type == WIN32S_TMPFILE) {
+		DeleteFile(((TmpFile*)filePtr)->name);
+	    }
+	    break;
+
+	case WIN32S_PIPE:
+	    pipePtr = (WinPipe *) file;
+
+	    if (pipePtr->otherPtr != NULL) {
+		pipePtr->otherPtr->otherPtr = NULL;
+	    } else {
+		if (pipePtr->file.handle != INVALID_HANDLE_VALUE) {
+		    CloseHandle(pipePtr->file.handle);
+		}
+		DeleteFile(pipePtr->fileName);
+		ckfree((char *) pipePtr->fileName);
+	    }
+	    break;
+
+	default:
+	    panic("Tcl_CloseFile: unexpected file type");
+    }
+
+    ckfree((char *) filePtr);
+    return 0;
+}
+
+/*
+ *--------------------------------------------------------------------------
+ *
+ * TclpGetPid --
+ *
+ *	Given a HANDLE to a child process, return the process id for that
+ *	child process.
+ *
+ * Results:
+ *	Returns the process id for the child process.  If the pid was not 
+ *	known by Tcl, either because the pid was not created by Tcl or the 
+ *	child process has already been reaped, -1 is returned.
+ *
+ * Side effects:
+ *	None.
+ *
+ *--------------------------------------------------------------------------
+ */
+
+unsigned long
+TclpGetPid(pid)
+    Tcl_Pid pid;		/* The HANDLE of the child process. */
+{
+    ProcInfo *infoPtr;
+    
+    for (infoPtr = procList; infoPtr != NULL; infoPtr = infoPtr->nextPtr) {
+	if (infoPtr->hProcess == (HANDLE) pid) {
+	    return infoPtr->dwProcessId;
+	}
+    }
+    return (unsigned long) -1;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclpCreateProcess --
+ *
+ *	Create a child process that has the specified files as its 
+ *	standard input, output, and error.  The child process runs
+ *	synchronously under Win32s and asynchronously under Windows NT
+ *	and Windows 95, and runs with the same environment variables
+ *	as the creating process.
+ *
+ *	The complete Windows search path is searched to find the specified 
+ *	executable.  If an executable by the given name is not found, 
+ *	automatically tries appending ".com", ".exe", and ".bat" to the 
+ *	executable name.
+ *
+ * Results:
+ *	The return value is TCL_ERROR and an error message is left in
+ *	interp->result if there was a problem creating the child 
+ *	process.  Otherwise, the return value is TCL_OK and *pidPtr is
+ *	filled with the process id of the child process.
+ * 
+ * Side effects:
+ *	A process is created.
+ *	
+ *----------------------------------------------------------------------
+ */
+
+int
+TclpCreateProcess(interp, argc, argv, inputFile, outputFile, errorFile, 
+	pidPtr)
+    Tcl_Interp *interp;		/* Interpreter in which to leave errors that
+				 * occurred when creating the child process.
+				 * Error messages from the child process
+				 * itself are sent to errorFile. */
+    int argc;			/* Number of arguments in following array. */
+    char **argv;		/* Array of argument strings.  argv[0]
+				 * contains the name of the executable
+				 * converted to native format (using the
+				 * Tcl_TranslateFileName call).  Additional
+				 * arguments have not been converted. */
+    TclFile inputFile;		/* If non-NULL, gives the file to use as
+				 * input for the child process.  If inputFile
+				 * file is not readable or is NULL, the child
+				 * will receive no standard input. */
+    TclFile outputFile;		/* If non-NULL, gives the file that
+				 * receives output from the child process.  If
+				 * outputFile file is not writeable or is
+				 * NULL, output from the child will be
+				 * discarded. */
+    TclFile errorFile;		/* If non-NULL, gives the file that
+				 * receives errors from the child process.  If
+				 * errorFile file is not writeable or is NULL,
+				 * errors from the child will be discarded.
+				 * errorFile may be the same as outputFile. */
+    Tcl_Pid *pidPtr;		/* If this procedure is successful, pidPtr
+				 * is filled with the process id of the child
+				 * process. */
+{
+    int result, applType, createFlags;
+    Tcl_DString cmdLine;
+    STARTUPINFO startInfo;
+    PROCESS_INFORMATION procInfo;
+    SECURITY_ATTRIBUTES secAtts;
+    HANDLE hProcess, h, inputHandle, outputHandle, errorHandle;
+    char execPath[MAX_PATH];
+    char *originalName;
+    WinFile *filePtr;
+
+    if (!initialized) {
+	PipeInit();
+    }
+
+    applType = ApplicationType(interp, argv[0], execPath);
+    if (applType == APPL_NONE) {
+	return TCL_ERROR;
+    }
+    originalName = argv[0];
+    argv[0] = execPath;
+
+    result = TCL_ERROR;
+    Tcl_DStringInit(&cmdLine);
+
+    if (TclWinGetPlatformId() == VER_PLATFORM_WIN32s) {
+	/*
+	 * Under Win32s, there are no pipes.  In order to simulate pipe
+	 * behavior, the child processes are run synchronously and their
+	 * I/O is redirected from/to temporary files before the next 
+	 * stage of the pipeline is started.
+	 */
+
+	MSG msg;
+	DWORD status;
+	DWORD args[4];
+	void *trans[5];
+	char *inputFileName, *outputFileName;
+	Tcl_DString inputTempFile, outputTempFile;
+
+	BuildCommandLine(argc, argv, &cmdLine);
+
+	ZeroMemory(&startInfo, sizeof(startInfo));
+	startInfo.cb = sizeof(startInfo);
+
+	Tcl_DStringInit(&inputTempFile);
+	Tcl_DStringInit(&outputTempFile);
+	outputHandle = INVALID_HANDLE_VALUE;
+
+	inputFileName = NULL;
+	outputFileName = NULL;
+	if (inputFile != NULL) {
+	    filePtr = (WinFile *) inputFile;
+	    switch (filePtr->type) {
+		case WIN_FILE:
+		case WIN32S_TMPFILE: {
+		    h = INVALID_HANDLE_VALUE;
+		    inputFileName = MakeTempFile(&inputTempFile);
+		    if (inputFileName != NULL) {
+			h = CreateFile(inputFileName, GENERIC_WRITE, 0, 
+				NULL, CREATE_ALWAYS, 0, NULL);
+		    }
+		    if (h == INVALID_HANDLE_VALUE) {
+			Tcl_AppendResult(interp, "couldn't duplicate input handle: ", 
+				Tcl_PosixError(interp), (char *) NULL);
+			goto end32s;
+		    }
+		    CopyChannel(h, filePtr->handle);
+		    CloseHandle(h);
+		    break;
+		}
+		case WIN32S_PIPE: {
+		    inputFileName = ((WinPipe*)inputFile)->fileName;
+		    break;
+		}
+	    }
+	}
+	if (inputFileName == NULL) {
+	    inputFileName = "nul";
+	}
+	if (outputFile != NULL) {
+	    filePtr = (WinFile *)outputFile;
+	    if (filePtr->type == WIN_FILE) {
+		outputFileName = MakeTempFile(&outputTempFile);
+		if (outputFileName == NULL) {
+		    Tcl_AppendResult(interp, "couldn't duplicate output handle: ",
+			    Tcl_PosixError(interp), (char *) NULL);
+		    goto end32s;
+		}
+		outputHandle = filePtr->handle;
+	    } else if (filePtr->type == WIN32S_PIPE) {
+		outputFileName = ((WinPipe*)outputFile)->fileName;
+	    }
+	}
+	if (outputFileName == NULL) {
+	    outputFileName = "nul";
+	}
+
+	if (applType == APPL_DOS) {
+	    args[0] = (DWORD) Tcl_DStringValue(&cmdLine);
+	    args[1] = (DWORD) inputFileName;
+	    args[2] = (DWORD) outputFileName;
+	    trans[0] = &args[0];
+	    trans[1] = &args[1];
+	    trans[2] = &args[2];
+	    trans[3] = NULL;
+	    if (TclWinSynchSpawn(args, 0, trans, pidPtr) != 0) {
+		result = TCL_OK;
+	    }
+	} else if (applType == APPL_WIN3X) {
+	    args[0] = (DWORD) Tcl_DStringValue(&cmdLine);
+	    trans[0] = &args[0];
+	    trans[1] = NULL;
+	    if (TclWinSynchSpawn(args, 1, trans, pidPtr) != 0) {
+		result = TCL_OK;
+	    }
+	} else {
+	    if (CreateProcess(NULL, Tcl_DStringValue(&cmdLine), NULL, NULL, 
+		    FALSE, DETACHED_PROCESS, NULL, NULL, &startInfo, 
+		    &procInfo) != 0) {
+		CloseHandle(procInfo.hThread);
+		while (1) {
+		    if (GetExitCodeProcess(procInfo.hProcess, &status) == FALSE) {
+			break;
+		    }
+		    if (status != STILL_ACTIVE) {
+			break;
+		    }
+		    if (PeekMessage(&msg, NULL, 0, 0, PM_REMOVE) == TRUE) {
+			TranslateMessage(&msg);
+			DispatchMessage(&msg);
+		    }
+		}
+		*pidPtr = (Tcl_Pid) procInfo.hProcess;
+		if (*pidPtr != 0) {
+		    ProcInfo *procPtr = (ProcInfo *) ckalloc(sizeof(ProcInfo));
+		    procPtr->hProcess = procInfo.hProcess;
+		    procPtr->dwProcessId = procInfo.dwProcessId;
+		    procPtr->nextPtr = procList;
+		    procList = procPtr;
+		}
+		result = TCL_OK;
+	    }
+	}
+	if (result != TCL_OK) {
+	    TclWinConvertError(GetLastError());
+	    Tcl_AppendResult(interp, "couldn't execute \"", originalName,
+		    "\": ", Tcl_PosixError(interp), (char *) NULL);
+	}
+
+	end32s:
+	if (outputHandle != INVALID_HANDLE_VALUE) {
+	    /*
+	     * Now copy stuff from temp file to actual output handle. Don't
+	     * close outputHandle because it is associated with the output
+	     * file owned by the caller.
+	     */
+
+	    h = CreateFile(outputFileName, GENERIC_READ, 0, NULL, OPEN_ALWAYS,
+		    0, NULL);
+	    if (h != INVALID_HANDLE_VALUE) {
+		CopyChannel(outputHandle, h);
+	    }
+	    CloseHandle(h);
+	}
+
+	if (inputFileName == Tcl_DStringValue(&inputTempFile)) {
+	    DeleteFile(inputFileName);
+	}
+	
+	if (outputFileName == Tcl_DStringValue(&outputTempFile)) {
+	    DeleteFile(outputFileName);
+	}
+
+	Tcl_DStringFree(&inputTempFile);
+	Tcl_DStringFree(&outputTempFile);
+        Tcl_DStringFree(&cmdLine);
+	return result;
+    }
+    hProcess = GetCurrentProcess();
+
+    /*
+     * STARTF_USESTDHANDLES must be used to pass handles to child process.
+     * Using SetStdHandle() and/or dup2() only works when a console mode 
+     * parent process is spawning an attached console mode child process.
+     */
+
+    ZeroMemory(&startInfo, sizeof(startInfo));
+    startInfo.cb = sizeof(startInfo);
+    startInfo.dwFlags   = STARTF_USESTDHANDLES;
+    startInfo.hStdInput	= INVALID_HANDLE_VALUE;
+    startInfo.hStdOutput= INVALID_HANDLE_VALUE;
+    startInfo.hStdError = INVALID_HANDLE_VALUE;
+
+    secAtts.nLength = sizeof(SECURITY_ATTRIBUTES);
+    secAtts.lpSecurityDescriptor = NULL;
+    secAtts.bInheritHandle = TRUE;
+
+    /*
+     * We have to check the type of each file, since we cannot duplicate 
+     * some file types.  
+     */
+
+    inputHandle = INVALID_HANDLE_VALUE;
+    if (inputFile != NULL) {
+	filePtr = (WinFile *)inputFile;
+	if (filePtr->type == WIN_FILE) {
+	    inputHandle = filePtr->handle;
+	}
+    }
+    outputHandle = INVALID_HANDLE_VALUE;
+    if (outputFile != NULL) {
+	filePtr = (WinFile *)outputFile;
+	if (filePtr->type == WIN_FILE) {
+	    outputHandle = filePtr->handle;
+	}
+    }
+    errorHandle = INVALID_HANDLE_VALUE;
+    if (errorFile != NULL) {
+	filePtr = (WinFile *)errorFile;
+	if (filePtr->type == WIN_FILE) {
+	    errorHandle = filePtr->handle;
+	}
+    }
+
+    /*
+     * Duplicate all the handles which will be passed off as stdin, stdout
+     * and stderr of the child process. The duplicate handles are set to
+     * be inheritable, so the child process can use them.
+     */
+
+    if (inputHandle == INVALID_HANDLE_VALUE) {
+	/* 
+	 * If handle was not set, stdin should return immediate EOF.
+	 * Under Windows95, some applications (both 16 and 32 bit!) 
+	 * cannot read from the NUL device; they read from console
+	 * instead.  When running tk, this is fatal because the child 
+	 * process would hang forever waiting for EOF from the unmapped 
+	 * console window used by the helper application.
+	 *
+	 * Fortunately, the helper application detects a closed pipe 
+	 * as an immediate EOF and can pass that information to the 
+	 * child process.
+	 */
+
+	if (CreatePipe(&startInfo.hStdInput, &h, &secAtts, 0) != FALSE) {
+	    CloseHandle(h);
+	}
+    } else {
+	DuplicateHandle(hProcess, inputHandle, hProcess, &startInfo.hStdInput,
+		0, TRUE, DUPLICATE_SAME_ACCESS);
+    }
+    if (startInfo.hStdInput == INVALID_HANDLE_VALUE) {
+	TclWinConvertError(GetLastError());
+	Tcl_AppendResult(interp, "couldn't duplicate input handle: ",
+		Tcl_PosixError(interp), (char *) NULL);
+	goto end;
+    }
+
+    if (outputHandle == INVALID_HANDLE_VALUE) {
+	/*
+	 * If handle was not set, output should be sent to an infinitely 
+	 * deep sink.  Under Windows 95, some 16 bit applications cannot
+	 * have stdout redirected to NUL; they send their output to
+	 * the console instead.  Some applications, like "more" or "dir /p", 
+	 * when outputting multiple pages to the console, also then try and
+	 * read from the console to go the next page.  When running tk, this
+	 * is fatal because the child process would hang forever waiting
+	 * for input from the unmapped console window used by the helper
+	 * application.
+	 *
+	 * Fortunately, the helper application will detect a closed pipe
+	 * as a sink.
+	 */
+
+	if ((TclWinGetPlatformId() == VER_PLATFORM_WIN32_WINDOWS) 
+		&& (applType == APPL_DOS)) {
+	    if (CreatePipe(&h, &startInfo.hStdOutput, &secAtts, 0) != FALSE) {
+		CloseHandle(h);
+	    }
+	} else {
+	    startInfo.hStdOutput = CreateFile("NUL:", GENERIC_WRITE, 0,
+		    &secAtts, OPEN_ALWAYS, FILE_ATTRIBUTE_NORMAL, NULL);
+	}
+    } else {
+	DuplicateHandle(hProcess, outputHandle, hProcess, &startInfo.hStdOutput, 
+		0, TRUE, DUPLICATE_SAME_ACCESS);
+    }
+    if (startInfo.hStdOutput == INVALID_HANDLE_VALUE) {
+	TclWinConvertError(GetLastError());
+	Tcl_AppendResult(interp, "couldn't duplicate output handle: ",
+		Tcl_PosixError(interp), (char *) NULL);
+	goto end;
+    }
+
+    if (errorHandle == INVALID_HANDLE_VALUE) {
+	/*
+	 * If handle was not set, errors should be sent to an infinitely
+	 * deep sink.
+	 */
+
+	startInfo.hStdError = CreateFile("NUL:", GENERIC_WRITE, 0,
+		&secAtts, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);
+    } else {
+	DuplicateHandle(hProcess, errorHandle, hProcess, &startInfo.hStdError, 
+		0, TRUE, DUPLICATE_SAME_ACCESS);
+    } 
+    if (startInfo.hStdError == INVALID_HANDLE_VALUE) {
+	TclWinConvertError(GetLastError());
+	Tcl_AppendResult(interp, "couldn't duplicate error handle: ",
+		Tcl_PosixError(interp), (char *) NULL);
+	goto end;
+    }
+    /* 
+     * If we do not have a console window, then we must run DOS and
+     * WIN32 console mode applications as detached processes. This tells
+     * the loader that the child application should not inherit the
+     * console, and that it should not create a new console window for
+     * the child application.  The child application should get its stdio 
+     * from the redirection handles provided by this application, and run
+     * in the background.
+     *
+     * If we are starting a GUI process, they don't automatically get a 
+     * console, so it doesn't matter if they are started as foreground or
+     * detached processes.  The GUI window will still pop up to the
+     * foreground.
+     */
+
+    if (TclWinGetPlatformId() == VER_PLATFORM_WIN32_NT) {
+	if (HasConsole()) {
+	    createFlags = 0;
+	} else if (applType == APPL_DOS) {
+	    /*
+	     * Under NT, 16-bit DOS applications will not run unless they
+	     * can be attached to a console.  If we are running without a
+	     * console, run the 16-bit program as an normal process inside
+	     * of a hidden console application, and then run that hidden
+	     * console as a detached process.
+	     */
+
+	    startInfo.wShowWindow = SW_HIDE;
+	    startInfo.dwFlags |= STARTF_USESHOWWINDOW;
+	    createFlags = CREATE_NEW_CONSOLE;
+	    Tcl_DStringAppend(&cmdLine, "cmd.exe /c ", -1);
+	} else {
+	    createFlags = DETACHED_PROCESS;
+	} 
+    } else {
+	if (HasConsole()) {
+	    createFlags = 0;
+	} else {
+	    createFlags = DETACHED_PROCESS;
+	}
+	
+	if (applType == APPL_DOS) {
+	    /*
+	     * Under Windows 95, 16-bit DOS applications do not work well 
+	     * with pipes:
+	     *
+	     * 1. EOF on a pipe between a detached 16-bit DOS application 
+	     * and another application is not seen at the other
+	     * end of the pipe, so the listening process blocks forever on 
+	     * reads.  This inablity to detect EOF happens when either a 
+	     * 16-bit app or the 32-bit app is the listener.  
+	     *
+	     * 2. If a 16-bit DOS application (detached or not) blocks when 
+	     * writing to a pipe, it will never wake up again, and it
+	     * eventually brings the whole system down around it.
+	     *
+	     * The 16-bit application is run as a normal process inside
+	     * of a hidden helper console app, and this helper may be run
+	     * as a detached process.  If any of the stdio handles is
+	     * a pipe, the helper application accumulates information 
+	     * into temp files and forwards it to or from the DOS 
+	     * application as appropriate.  This means that DOS apps 
+	     * must receive EOF from a stdin pipe before they will actually
+	     * begin, and must finish generating stdout or stderr before 
+	     * the data will be sent to the next stage of the pipe.
+	     *
+	     * The helper app should be located in the same directory as
+	     * the tcl dll.
+	     */
+
+	    if (createFlags != 0) {
+		startInfo.wShowWindow = SW_HIDE;
+		startInfo.dwFlags |= STARTF_USESHOWWINDOW;
+		createFlags = CREATE_NEW_CONSOLE;
+	    }
+	    Tcl_DStringAppend(&cmdLine, "tclpip" STRINGIFY(TCL_MAJOR_VERSION) 
+		    STRINGIFY(TCL_MINOR_VERSION) ".dll ", -1);
+	}
+    }
+    
+    /*
+     * cmdLine gets the full command line used to invoke the executable,
+     * including the name of the executable itself.  The command line
+     * arguments in argv[] are stored in cmdLine separated by spaces. 
+     * Special characters in individual arguments from argv[] must be 
+     * quoted when being stored in cmdLine.
+     *
+     * When calling any application, bear in mind that arguments that 
+     * specify a path name are not converted.  If an argument contains 
+     * forward slashes as path separators, it may or may not be 
+     * recognized as a path name, depending on the program.  In general,
+     * most applications accept forward slashes only as option 
+     * delimiters and backslashes only as paths.
+     *
+     * Additionally, when calling a 16-bit dos or windows application, 
+     * all path names must use the short, cryptic, path format (e.g., 
+     * using ab~1.def instead of "a b.default").  
+     */
+
+    BuildCommandLine(argc, argv, &cmdLine);
+
+    if (!CreateProcess(NULL, Tcl_DStringValue(&cmdLine), NULL, NULL, TRUE, 
+	    createFlags, NULL, NULL, &startInfo, &procInfo)) {
+	TclWinConvertError(GetLastError());
+	Tcl_AppendResult(interp, "couldn't execute \"", originalName,
+		"\": ", Tcl_PosixError(interp), (char *) NULL);
+	goto end;
+    }
+
+    if (applType == APPL_DOS) {
+	WaitForSingleObject(hProcess, 50);
+    }
+
+    /* 
+     * "When an application spawns a process repeatedly, a new thread 
+     * instance will be created for each process but the previous 
+     * instances may not be cleaned up.  This results in a significant 
+     * virtual memory loss each time the process is spawned.  If there 
+     * is a WaitForInputIdle() call between CreateProcess() and
+     * CloseHandle(), the problem does not occur." PSS ID Number: Q124121
+     */
+
+    WaitForInputIdle(procInfo.hProcess, 5000);
+    CloseHandle(procInfo.hThread);
+
+    *pidPtr = (Tcl_Pid) procInfo.hProcess;
+    if (*pidPtr != 0) {
+	ProcInfo *procPtr = (ProcInfo *) ckalloc(sizeof(ProcInfo));
+	procPtr->hProcess = procInfo.hProcess;
+	procPtr->dwProcessId = procInfo.dwProcessId;
+	procPtr->nextPtr = procList;
+	procList = procPtr;
+    }
+    result = TCL_OK;
+
+    end:
+    Tcl_DStringFree(&cmdLine);
+    if (startInfo.hStdInput != INVALID_HANDLE_VALUE) {
+        CloseHandle(startInfo.hStdInput);
+    }
+    if (startInfo.hStdOutput != INVALID_HANDLE_VALUE) {
+        CloseHandle(startInfo.hStdOutput);
+    }
+    if (startInfo.hStdError != INVALID_HANDLE_VALUE) {
+	CloseHandle(startInfo.hStdError);
+    }
+    return result;
+}
+
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * HasConsole --
+ *
+ *	Determines whether the current application is attached to a
+ *	console.
+ *
+ * Results:
+ *	Returns TRUE if this application has a console, else FALSE.
+ *
+ * Side effects:
+ *	None.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static BOOL
+HasConsole()
+{
+    HANDLE handle = CreateFile("CONOUT$", GENERIC_WRITE, FILE_SHARE_WRITE,
+	    NULL, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);
+
+    if (handle != INVALID_HANDLE_VALUE) {
+        CloseHandle(handle);
+	return TRUE;
+    } else {
+        return FALSE;
+    }
+}
+
+/*
+ *--------------------------------------------------------------------
+ *
+ * ApplicationType --
+ *
+ *	Search for the specified program and identify if it refers to a DOS,
+ *	Windows 3.X, or Win32 program.  Used to determine how to invoke 
+ *	a program, or if it can even be invoked.
+ *
+ *	It is possible to almost positively identify DOS and Windows 
+ *	applications that contain the appropriate magic numbers.  However, 
+ *	DOS .com files do not seem to contain a magic number; if the program 
+ *	name ends with .com and could not be identified as a Windows .com
+ *	file, it will be assumed to be a DOS application, even if it was
+ *	just random data.  If the program name does not end with .com, no 
+ *	such assumption is made.
+ *
+ *	The Win32 procedure GetBinaryType incorrectly identifies any 
+ *	junk file that ends with .exe as a dos executable and some 
+ *	executables that don't end with .exe as not executable.  Plus it 
+ *	doesn't exist under win95, so I won't feel bad about reimplementing
+ *	functionality.
+ *
+ * Results:
+ *	The return value is one of APPL_DOS, APPL_WIN3X, or APPL_WIN32
+ *	if the filename referred to the corresponding application type.
+ *	If the file name could not be found or did not refer to any known 
+ *	application type, APPL_NONE is returned and an error message is 
+ *	left in interp.  .bat files are identified as APPL_DOS.
+ *
+ * Side effects:
+ *	None.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static int
+ApplicationType(interp, originalName, fullPath)
+    Tcl_Interp *interp;		/* Interp, for error message. */
+    const char *originalName;	/* Name of the application to find. */
+    char fullPath[MAX_PATH];	/* Filled with complete path to 
+				 * application. */
+{
+    int applType, i;
+    HANDLE hFile;
+    char *ext, *rest;
+    char buf[2];
+    DWORD read;
+    IMAGE_DOS_HEADER header;
+    static char extensions[][5] = {"", ".com", ".exe", ".bat"};
+
+    /* Look for the program as an external program.  First try the name
+     * as it is, then try adding .com, .exe, and .bat, in that order, to
+     * the name, looking for an executable.
+     *
+     * Using the raw SearchPath() procedure doesn't do quite what is 
+     * necessary.  If the name of the executable already contains a '.' 
+     * character, it will not try appending the specified extension when
+     * searching (in other words, SearchPath will not find the program 
+     * "a.b.exe" if the arguments specified "a.b" and ".exe").   
+     * So, first look for the file as it is named.  Then manually append 
+     * the extensions, looking for a match.  
+     */
+
+    applType = APPL_NONE;
+    for (i = 0; i < (int) (sizeof(extensions) / sizeof(extensions[0])); i++) {
+	lstrcpyn(fullPath, originalName, MAX_PATH - 5);
+        lstrcat(fullPath, extensions[i]);
+	
+	SearchPath(NULL, fullPath, NULL, MAX_PATH, fullPath, &rest);
+
+	/*
+	 * Ignore matches on directories or data files, return if identified
+	 * a known type.
+	 */
+
+	if (GetFileAttributes(fullPath) & FILE_ATTRIBUTE_DIRECTORY) {
+	    continue;
+	}
+
+	ext = strrchr(fullPath, '.');
+	if ((ext != NULL) && (strcmpi(ext, ".bat") == 0)) {
+	    applType = APPL_DOS;
+	    break;
+	}
+
+	hFile = CreateFile(fullPath, GENERIC_READ, FILE_SHARE_READ, NULL, 
+		OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);
+	if (hFile == INVALID_HANDLE_VALUE) {
+	    continue;
+	}
+
+	header.e_magic = 0;
+	ReadFile(hFile, (void *) &header, sizeof(header), &read, NULL);
+	if (header.e_magic != IMAGE_DOS_SIGNATURE) {
+	    /* 
+	     * Doesn't have the magic number for relocatable executables.  If 
+	     * filename ends with .com, assume it's a DOS application anyhow.
+	     * Note that we didn't make this assumption at first, because some
+	     * supposed .com files are really 32-bit executables with all the
+	     * magic numbers and everything.  
+	     */
+
+	    CloseHandle(hFile);
+	    if ((ext != NULL) && (strcmpi(ext, ".com") == 0)) {
+		applType = APPL_DOS;
+		break;
+	    }
+	    continue;
+	}
+	if (header.e_lfarlc != sizeof(header)) {
+	    /* 
+	     * All Windows 3.X and Win32 and some DOS programs have this value
+	     * set here.  If it doesn't, assume that since it already had the 
+	     * other magic number it was a DOS application.
+	     */
+
+	    CloseHandle(hFile);
+	    applType = APPL_DOS;
+	    break;
+	}
+
+	/* 
+	 * The DWORD at header.e_lfanew points to yet another magic number.
+	 */
+
+	buf[0] = '\0';
+	SetFilePointer(hFile, header.e_lfanew, NULL, FILE_BEGIN);
+	ReadFile(hFile, (void *) buf, 2, &read, NULL);
+	CloseHandle(hFile);
+
+	if ((buf[0] == 'N') && (buf[1] == 'E')) {
+	    applType = APPL_WIN3X;
+	} else if ((buf[0] == 'P') && (buf[1] == 'E')) {
+	    applType = APPL_WIN32;
+	} else {
+	    /*
+	     * Strictly speaking, there should be a test that there
+	     * is an 'L' and 'E' at buf[0..1], to identify the type as 
+	     * DOS, but of course we ran into a DOS executable that 
+	     * _doesn't_ have the magic number -- specifically, one
+	     * compiled using the Lahey Fortran90 compiler.
+	     */
+
+	    applType = APPL_DOS;
+	}
+	break;
+    }
+
+    if (applType == APPL_NONE) {
+	TclWinConvertError(GetLastError());
+	Tcl_AppendResult(interp, "couldn't execute \"", originalName,
+		"\": ", Tcl_PosixError(interp), (char *) NULL);
+	return APPL_NONE;
+    }
+
+    if ((applType == APPL_DOS) || (applType == APPL_WIN3X)) {
+	/* 
+	 * Replace long path name of executable with short path name for 
+	 * 16-bit applications.  Otherwise the application may not be able
+	 * to correctly parse its own command line to separate off the 
+	 * application name from the arguments.
+	 */
+
+	GetShortPathName(fullPath, fullPath, MAX_PATH);
+    }
+    return applType;
+}
+
+/*    
+ *----------------------------------------------------------------------
+ *
+ * BuildCommandLine --
+ *
+ *	The command line arguments are stored in linePtr separated
+ *	by spaces, in a form that CreateProcess() understands.  Special 
+ *	characters in individual arguments from argv[] must be quoted 
+ *	when being stored in cmdLine.
+ *
+ * Results:
+ *	None.
+ *
+ * Side effects:
+ *	None.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static void
+BuildCommandLine(argc, argv, linePtr)
+    int argc;			/* Number of arguments. */
+    char **argv;		/* Argument strings. */
+    Tcl_DString *linePtr;	/* Initialized Tcl_DString that receives the
+				 * command line. */
+{
+    char *start, *special;
+    int quote, i;
+
+    for (i = 0; i < argc; i++) {
+	if (i > 0) {
+	    Tcl_DStringAppend(linePtr, " ", 1);	
+	}
+
+	quote = 0;
+	for (start = argv[i]; *start != '\0'; start++) {
+	    if (isspace(*start)) {
+		quote = 1;
+		Tcl_DStringAppend(linePtr, "\"", 1);
+    		break;
+	    }
+	}
+
+	start = argv[i];	    
+	for (special = argv[i]; ; ) {
+	    if ((*special == '\\') && 
+		    (special[1] == '\\' || special[1] == '"')) {
+		Tcl_DStringAppend(linePtr, start, special - start);
+		start = special;
+		while (1) {
+		    special++;
+		    if (*special == '"') {
+			/* 
+			 * N backslashes followed a quote -> insert 
+			 * N * 2 + 1 backslashes then a quote.
+			 */
+
+			Tcl_DStringAppend(linePtr, start, special - start);
+			break;
+		    }
+		    if (*special != '\\') {
+			break;
+		    }
+		}
+		Tcl_DStringAppend(linePtr, start, special - start);
+		start = special;
+	    }
+	    if (*special == '"') {
+		Tcl_DStringAppend(linePtr, start, special - start);
+		Tcl_DStringAppend(linePtr, "\\\"", 2);
+		start = special + 1;
+	    }
+	    if (*special == '\0') {
+		break;
+	    }
+	    special++;
+	}
+	Tcl_DStringAppend(linePtr, start, special - start);
+	if (quote) {
+	    Tcl_DStringAppend(linePtr, "\"", 1);
+	}
+    }
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * MakeTempFile --
+ *
+ *	Helper function for TclpCreateProcess under Win32s.  Makes a 
+ *	temporary file that _won't_ go away automatically when it's file
+ *	handle is closed.  Used for simulated pipes, which are written
+ *	in one pass and reopened and read in the next pass.
+ *
+ * Results:
+ *	namePtr is filled with the name of the temporary file.
+ *
+ * Side effects:
+ *	A temporary file with the name specified by namePtr is created.  
+ *	The caller is responsible for deleting this temporary file.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static char *
+MakeTempFile(namePtr)
+    Tcl_DString *namePtr;	/* Initialized Tcl_DString that is filled 
+				 * with the name of the temporary file that 
+				 * was created. */
+{
+    char name[MAX_PATH];
+
+    if (TempFileName(name) == 0) {
+	return NULL;
+    }
+
+    Tcl_DStringAppend(namePtr, name, -1);
+    return Tcl_DStringValue(namePtr);
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * CopyChannel --
+ *
+ *	Helper function used by TclpCreateProcess under Win32s.  Copies
+ *	what remains of source file to destination file; source file 
+ *	pointer need not be positioned at the beginning of the file if
+ *	all of source file is not desired, but data is copied up to end 
+ *	of source file.
+ *
+ * Results:
+ *	None.
+ *
+ * Side effects:
+ *	None.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static void
+CopyChannel(dst, src)
+    HANDLE dst;			/* Destination file. */
+    HANDLE src;			/* Source file. */
+{
+    char buf[8192];
+    DWORD dwRead, dwWrite;
+
+    while (ReadFile(src, buf, sizeof(buf), &dwRead, NULL) != FALSE) {
+	if (dwRead == 0) {
+	    break;
+	}
+	if (WriteFile(dst, buf, dwRead, &dwWrite, NULL) == FALSE) {
+	    break;
+	}
+    }
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclpCreateCommandChannel --
+ *
+ *	This function is called by Tcl_OpenCommandChannel to perform
+ *	the platform specific channel initialization for a command
+ *	channel.
+ *
+ * Results:
+ *	Returns a new channel or NULL on failure.
+ *
+ * Side effects:
+ *	Allocates a new channel.
+ *
+ *----------------------------------------------------------------------
+ */
+
+Tcl_Channel
+TclpCreateCommandChannel(readFile, writeFile, errorFile, numPids, pidPtr)
+    TclFile readFile;		/* If non-null, gives the file for reading. */
+    TclFile writeFile;		/* If non-null, gives the file for writing. */
+    TclFile errorFile;		/* If non-null, gives the file where errors
+				 * can be read. */
+    int numPids;		/* The number of pids in the pid array. */
+    Tcl_Pid *pidPtr;		/* An array of process identifiers. */
+{
+    char channelName[20];
+    int channelId;
+    PipeInfo *infoPtr = (PipeInfo *) ckalloc((unsigned) sizeof(PipeInfo));
+
+    if (!initialized) {
+	PipeInit();
+    }
+
+    infoPtr->watchMask = 0;
+    infoPtr->flags = 0;
+    infoPtr->readFile = readFile;
+    infoPtr->writeFile = writeFile;
+    infoPtr->errorFile = errorFile;
+    infoPtr->numPids = numPids;
+    infoPtr->pidPtr = pidPtr;
+
+    /*
+     * Use one of the fds associated with the channel as the
+     * channel id.
+     */
+
+    if (readFile) {
+	WinPipe *pipePtr = (WinPipe *) readFile;
+	if (pipePtr->file.type == WIN32S_PIPE
+		&& pipePtr->file.handle == INVALID_HANDLE_VALUE) {
+	    pipePtr->file.handle = CreateFile(pipePtr->fileName, GENERIC_READ,
+		    0, NULL, OPEN_ALWAYS, FILE_ATTRIBUTE_NORMAL, NULL);
+	}
+	channelId = (int) pipePtr->file.handle;
+    } else if (writeFile) {
+	channelId = (int) ((WinFile*)writeFile)->handle;
+    } else if (errorFile) {
+	channelId = (int) ((WinFile*)errorFile)->handle;
+    } else {
+	channelId = 0;
+    }
+
+    infoPtr->validMask = 0;
+    if (readFile != NULL) {
+        infoPtr->validMask |= TCL_READABLE;
+    }
+    if (writeFile != NULL) {
+        infoPtr->validMask |= TCL_WRITABLE;
+    }
+
+    /*
+     * For backward compatibility with previous versions of Tcl, we
+     * use "file%d" as the base name for pipes even though it would
+     * be more natural to use "pipe%d".
+     */
+
+    sprintf(channelName, "file%d", channelId);
+    infoPtr->channel = Tcl_CreateChannel(&pipeChannelType, channelName,
+            (ClientData) infoPtr, infoPtr->validMask);
+
+    /*
+     * Pipes have AUTO translation mode on Windows and ^Z eof char, which
+     * means that a ^Z will be appended to them at close. This is needed
+     * for Windows programs that expect a ^Z at EOF.
+     */
+
+    Tcl_SetChannelOption((Tcl_Interp *) NULL, infoPtr->channel,
+	    "-translation", "auto");
+    Tcl_SetChannelOption((Tcl_Interp *) NULL, infoPtr->channel,
+	    "-eofchar", "\032 {}");
+    return infoPtr->channel;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclGetAndDetachPids --
+ *
+ *	Stores a list of the command PIDs for a command channel in
+ *	interp->result.
+ *
+ * Results:
+ *	None.
+ *
+ * Side effects:
+ *	Modifies interp->result.
+ *
+ *----------------------------------------------------------------------
+ */
+
+void
+TclGetAndDetachPids(interp, chan)
+    Tcl_Interp *interp;
+    Tcl_Channel chan;
+{
+    PipeInfo *pipePtr;
+    Tcl_ChannelType *chanTypePtr;
+    int i;
+    char buf[20];
+
+    /*
+     * Punt if the channel is not a command channel.
+     */
+
+    chanTypePtr = Tcl_GetChannelType(chan);
+    if (chanTypePtr != &pipeChannelType) {
+        return;
+    }
+
+    pipePtr = (PipeInfo *) Tcl_GetChannelInstanceData(chan);
+    for (i = 0; i < pipePtr->numPids; i++) {
+        sprintf(buf, "%lu", TclpGetPid(pipePtr->pidPtr[i]));
+        Tcl_AppendElement(interp, buf);
+        Tcl_DetachPids(1, &(pipePtr->pidPtr[i]));
+    }
+    if (pipePtr->numPids > 0) {
+        ckfree((char *) pipePtr->pidPtr);
+        pipePtr->numPids = 0;
+    }
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * PipeBlockModeProc --
+ *
+ *	Set blocking or non-blocking mode on channel.
+ *
+ * Results:
+ *	0 if successful, errno when failed.
+ *
+ * Side effects:
+ *	Sets the device into blocking or non-blocking mode.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static int
+PipeBlockModeProc(instanceData, mode)
+    ClientData 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,
+     * hence we have to emulate the behavior. This is done in the input
+     * function by checking against a bit in the state. We set or unset the
+     * bit here to cause the input function to emulate the correct behavior.
+     */
+
+    if (mode == TCL_MODE_NONBLOCKING) {
+	infoPtr->flags |= PIPE_ASYNC;
+    } else {
+	infoPtr->flags &= ~(PIPE_ASYNC);
+    }
+    return 0;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * PipeCloseProc --
+ *
+ *	Closes a pipe based IO channel.
+ *
+ * Results:
+ *	0 on success, errno otherwise.
+ *
+ * Side effects:
+ *	Closes the physical channel.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static int
+PipeCloseProc(instanceData, interp)
+    ClientData instanceData;	/* Pointer to PipeInfo structure. */
+    Tcl_Interp *interp;		/* For error reporting. */
+{
+    PipeInfo *pipePtr = (PipeInfo *) instanceData;
+    Tcl_Channel errChan;
+    int errorCode, result;
+    PipeInfo *infoPtr, **nextPtrPtr;
+
+    /*
+     * Remove the file from the list of watched files.
+     */
+
+    for (nextPtrPtr = &firstPipePtr, infoPtr = *nextPtrPtr; infoPtr != NULL;
+	    nextPtrPtr = &infoPtr->nextPtr, infoPtr = *nextPtrPtr) {
+	if (infoPtr == (PipeInfo *)pipePtr) {
+	    *nextPtrPtr = infoPtr->nextPtr;
+	    break;
+	}
+    }
+
+    errorCode = 0;
+    if (pipePtr->readFile != NULL) {
+	if (TclpCloseFile(pipePtr->readFile) != 0) {
+	    errorCode = errno;
+	}
+    }
+    if (pipePtr->writeFile != NULL) {
+	if (TclpCloseFile(pipePtr->writeFile) != 0) {
+	    if (errorCode == 0) {
+		errorCode = errno;
+	    }
+	}
+    }
+    
+    /*
+     * Wrap the error file into a channel and give it to the cleanup
+     * routine.  If we are running in Win32s, just delete the error file
+     * immediately, because it was never used.
+     */
+
+    if (pipePtr->errorFile) {
+	WinFile *filePtr;
+	OSVERSIONINFO os;
+
+	os.dwOSVersionInfoSize = sizeof(os);
+	GetVersionEx(&os);
+	if (os.dwPlatformId == VER_PLATFORM_WIN32s) {
+	    TclpCloseFile(pipePtr->errorFile);
+	    errChan = NULL;
+	} else {
+	    filePtr = (WinFile*)pipePtr->errorFile;
+	    errChan = Tcl_MakeFileChannel((ClientData) filePtr->handle,
+		    TCL_READABLE);
+	}
+    } else {
+        errChan = NULL;
+    }
+    result = TclCleanupChildren(interp, pipePtr->numPids, pipePtr->pidPtr,
+            errChan);
+    if (pipePtr->numPids > 0) {
+        ckfree((char *) pipePtr->pidPtr);
+    }
+    ckfree((char*) pipePtr);
+
+    if (errorCode == 0) {
+        return result;
+    }
+    return errorCode;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * PipeInputProc --
+ *
+ *	Reads input from the IO channel into the buffer given. Returns
+ *	count of how many bytes were actually read, and an error indication.
+ *
+ * Results:
+ *	A count of how many bytes were read is returned and an error
+ *	indication is returned in an output argument.
+ *
+ * Side effects:
+ *	Reads input from the actual channel.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static int
+PipeInputProc(instanceData, buf, bufSize, errorCode)
+    ClientData 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;
+    DWORD count;
+    DWORD bytesRead;
+
+    *errorCode = 0;
+    if (filePtr->type == WIN32S_PIPE) {
+	if (((WinPipe *)filePtr)->otherPtr != NULL) {
+	    panic("PipeInputProc: child process isn't finished writing");
+	}
+	if (filePtr->handle == INVALID_HANDLE_VALUE) {
+	    filePtr->handle = CreateFile(((WinPipe *)filePtr)->fileName,
+		    GENERIC_READ, 0, NULL, OPEN_ALWAYS, FILE_ATTRIBUTE_NORMAL,
+		    NULL);
+	}
+	if (filePtr->handle == INVALID_HANDLE_VALUE) {
+	    goto error;
+	}
+    } else {
+	/*
+	 * Pipes will block until the requested number of bytes has been
+	 * read.  To avoid blocking unnecessarily, we look ahead and only
+	 * read as much as is available.
+	 */
+
+	if (PeekNamedPipe(filePtr->handle, (LPVOID) NULL, (DWORD) 0,
+		(LPDWORD) NULL, &count, (LPDWORD) NULL) == TRUE) {
+	    if ((count != 0) && ((DWORD) bufSize > count)) {
+		bufSize = (int) count;
+
+		/*
+		 * This code is commented out because on Win95 we don't get
+		 * notifier of eof on a pipe unless we try to read it.
+		 * The correct solution is to move to threads.
+		 */
+
+/* 	    } else if ((count == 0) && (infoPtr->flags & PIPE_ASYNC)) { */
+/* 		errno = *errorCode = EAGAIN; */
+/* 		return -1; */
+	    } else if ((count == 0) && !(infoPtr->flags & PIPE_ASYNC)) {
+		bufSize = 1;
+	    }
+	} else {
+	    goto error;
+	}
+    }
+
+    /*
+     * Note that we will block on reads from a console buffer until a
+     * full line has been entered.  The only way I know of to get
+     * around this is to write a console driver.  We should probably
+     * do this at some point, but for now, we just block.
+     */
+
+    if (ReadFile(filePtr->handle, (LPVOID) buf, (DWORD) bufSize, &bytesRead,
+            (LPOVERLAPPED) NULL) == FALSE) {
+	goto error;
+    }
+    
+    return bytesRead;
+
+    error:
+    TclWinConvertError(GetLastError());
+    if (errno == EPIPE) {
+	return 0;
+    }
+    *errorCode = errno;
+    return -1;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * PipeOutputProc --
+ *
+ *	Writes the given output on the IO channel. Returns count of how
+ *	many characters were actually written, and an error indication.
+ *
+ * Results:
+ *	A count of how many characters were written is returned and an
+ *	error indication is returned in an output argument.
+ *
+ * Side effects:
+ *	Writes output on the actual channel.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static int
+PipeOutputProc(instanceData, buf, toWrite, errorCode)
+    ClientData instanceData;		/* Pipe state. */
+    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;
+    
+    *errorCode = 0;
+    if (WriteFile(filePtr->handle, (LPVOID) buf, (DWORD) toWrite,
+	    &bytesWritten, (LPOVERLAPPED) NULL) == FALSE) {
+        TclWinConvertError(GetLastError());
+        if (errno == EPIPE) {
+            return 0;
+        }
+        *errorCode = errno;
+        return -1;
+    }
+    return bytesWritten;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * PipeEventProc --
+ *
+ *	This function is invoked by Tcl_ServiceEvent when a file event
+ *	reaches the front of the event queue.  This procedure invokes
+ *	Tcl_NotifyChannel on the pipe.
+ *
+ * Results:
+ *	Returns 1 if the event was handled, meaning it should be removed
+ *	from the queue.  Returns 0 if the event was not handled, meaning
+ *	it should stay on the queue.  The only time the event isn't
+ *	handled is if the TCL_FILE_EVENTS flag bit isn't set.
+ *
+ * Side effects:
+ *	Whatever the notifier callback does.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static int
+PipeEventProc(evPtr, flags)
+    Tcl_Event *evPtr;		/* Event to service. */
+    int flags;			/* Flags that indicate what events to
+				 * handle, such as TCL_FILE_EVENTS. */
+{
+    PipeEvent *pipeEvPtr = (PipeEvent *)evPtr;
+    PipeInfo *infoPtr;
+    WinFile *filePtr;
+    int mask;
+/*    DWORD count;*/
+
+    if (!(flags & TCL_FILE_EVENTS)) {
+	return 0;
+    }
+
+    /*
+     * Search through the list of watched pipes for the one whose handle
+     * matches the event.  We do this rather than simply dereferencing
+     * the handle in the event so that pipes can be deleted while the
+     * event is in the queue.
+     */
+
+    for (infoPtr = firstPipePtr; infoPtr != NULL; infoPtr = infoPtr->nextPtr) {
+	if (pipeEvPtr->infoPtr == infoPtr) {
+	    infoPtr->flags &= ~(PIPE_PENDING);
+	    break;
+	}
+    }
+
+    /*
+     * Remove stale events.
+     */
+
+    if (!infoPtr) {
+	return 1;
+    }
+
+    /*
+     * If we aren't on Win32s, check to see if the pipe is readable.  Note
+     * that we can't tell if a pipe is writable, so we always report it
+     * as being writable.
+     */
+
+    filePtr = (WinFile*) ((PipeInfo*)infoPtr)->readFile;
+    if (filePtr->type != WIN32S_PIPE) {
+
+	/*
+	 * On windows 95, PeekNamedPipe returns 0 on eof so we can't
+	 * distinguish underflow from eof.  The correct solution is to
+	 * switch to the threaded implementation.
+	 */
+	mask = TCL_WRITABLE|TCL_READABLE;
+/* 	if (PeekNamedPipe(filePtr->handle, (LPVOID) NULL, (DWORD) 0, */
+/* 		(LPDWORD) NULL, &count, (LPDWORD) NULL) == TRUE) { */
+/* 	    if (count != 0) { */
+/* 		mask |= TCL_READABLE; */
+/* 	    } */
+/* 	} else { */
+
+	    /*
+	     * If the pipe has been closed by the other side, then 
+	     * mark the pipe as readable, but not writable.
+	     */
+
+/* 	    if (GetLastError() == ERROR_BROKEN_PIPE) { */
+/* 		mask = TCL_READABLE; */
+/* 	    } */
+/* 	} */
+    } else {
+	mask = TCL_READABLE | TCL_WRITABLE;
+    }
+
+    /*
+     * Inform the channel of the events.
+     */
+
+    Tcl_NotifyChannel(infoPtr->channel, infoPtr->watchMask & mask);
+    return 1;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * PipeWatchProc --
+ *
+ *	Called by the notifier to set up to watch for events on this
+ *	channel.
+ *
+ * Results:
+ *	None.
+ *
+ * Side effects:
+ *	None.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static void
+PipeWatchProc(instanceData, mask)
+    ClientData 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;
+
+    /*
+     * For now, we just send a message to ourselves so we can poll the
+     * channel for readable events.
+     */
+
+    infoPtr->watchMask = mask & infoPtr->validMask;
+    if (infoPtr->watchMask) {
+	Tcl_Time blockTime = { 0, 0 };
+	if (!oldMask) {
+	    infoPtr->nextPtr = firstPipePtr;
+	    firstPipePtr = infoPtr;
+	}
+	Tcl_SetMaxBlockTime(&blockTime);
+    } else {
+	if (oldMask) {
+	    /*
+	     * Remove the pipe from the list of watched pipes.
+	     */
+
+	    for (nextPtrPtr = &firstPipePtr, ptr = *nextPtrPtr;
+		 ptr != NULL;
+		 nextPtrPtr = &ptr->nextPtr, ptr = *nextPtrPtr) {
+		if (infoPtr == ptr) {
+		    *nextPtrPtr = ptr->nextPtr;
+		    break;
+		}
+	    }
+	}
+    }
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * PipeGetHandleProc --
+ *
+ *	Called from Tcl_GetChannelHandle to retrieve OS handles from
+ *	inside a command pipeline based channel.
+ *
+ * Results:
+ *	Returns TCL_OK with the fd in handlePtr, or TCL_ERROR if
+ *	there is no handle for the specified direction. 
+ *
+ * Side effects:
+ *	None.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static int
+PipeGetHandleProc(instanceData, direction, handlePtr)
+    ClientData instanceData;	/* The pipe state. */
+    int direction;		/* TCL_READABLE or TCL_WRITABLE */
+    ClientData *handlePtr;	/* Where to store the handle.  */
+{
+    PipeInfo *infoPtr = (PipeInfo *) instanceData;
+    WinFile *filePtr; 
+
+    if (direction == TCL_READABLE && infoPtr->readFile) {
+	filePtr = (WinFile*) infoPtr->readFile;
+	if (filePtr->type == WIN32S_PIPE) {
+	    if (filePtr->handle == INVALID_HANDLE_VALUE) {
+		filePtr->handle = CreateFile(((WinPipe *)filePtr)->fileName,
+			GENERIC_READ, 0, NULL, OPEN_ALWAYS,
+			FILE_ATTRIBUTE_NORMAL, NULL);
+	    }
+	    if (filePtr->handle == INVALID_HANDLE_VALUE) {
+		return TCL_ERROR;
+	    }
+	}
+	*handlePtr = (ClientData) filePtr->handle;
+	return TCL_OK;
+    }
+    if (direction == TCL_WRITABLE && infoPtr->writeFile) {
+	filePtr = (WinFile*) infoPtr->writeFile;
+	*handlePtr = (ClientData) filePtr->handle;
+	return TCL_OK;
+    }
+    return TCL_ERROR;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * Tcl_WaitPid --
+ *
+ *	Emulates the waitpid system call.
+ *
+ * Results:
+ *	Returns 0 if the process is still alive, -1 on an error, or
+ *	the pid on a clean close.  
+ *
+ * Side effects:
+ *	Unless WNOHANG is set and the wait times out, the process
+ *	information record will be deleted and the process handle
+ *	will be closed.
+ *
+ *----------------------------------------------------------------------
+ */
+
+Tcl_Pid
+Tcl_WaitPid(pid, statPtr, options)
+    Tcl_Pid pid;
+    int *statPtr;
+    int options;
+{
+    ProcInfo *infoPtr, **prevPtrPtr;
+    int flags;
+    Tcl_Pid result;
+    DWORD ret;
+
+    if (!initialized) {
+	PipeInit();
+    }
+
+    /*
+     * If no pid is specified, do nothing.
+     */
+    
+    if (pid == 0) {
+	*statPtr = 0;
+	return 0;
+    }
+
+    /*
+     * Find the process on the process list.
+     */
+
+    prevPtrPtr = &procList;
+    for (infoPtr = procList; infoPtr != NULL;
+	    prevPtrPtr = &infoPtr->nextPtr, infoPtr = infoPtr->nextPtr) {
+	 if (infoPtr->hProcess == (HANDLE) pid) {
+	    break;
+	}
+    }
+
+    /*
+     * If the pid is not one of the processes we know about (we started it)
+     * then do nothing.
+     */
+    
+    if (infoPtr == NULL) {
+        *statPtr = 0;
+	return 0;
+    }
+
+    /*
+     * Officially "wait" for it to finish. We either poll (WNOHANG) or
+     * wait for an infinite amount of time.
+     */
+    
+    if (options & WNOHANG) {
+	flags = 0;
+    } else {
+	flags = INFINITE;
+    }
+    ret = WaitForSingleObject(infoPtr->hProcess, flags);
+    if (ret == WAIT_TIMEOUT) {
+	*statPtr = 0;
+	if (options & WNOHANG) {
+	    return 0;
+	} else {
+	    result = 0;
+	}
+    } else if (ret != WAIT_FAILED) {
+	GetExitCodeProcess(infoPtr->hProcess, (DWORD*)statPtr);
+	*statPtr = ((*statPtr << 8) & 0xff00);
+	result = pid;
+    } else {
+	errno = ECHILD;
+        *statPtr = ECHILD;
+	result = (Tcl_Pid) -1;
+    }
+
+    /*
+     * Remove the process from the process list and close the process handle.
+     */
+
+    CloseHandle(infoPtr->hProcess);
+    *prevPtrPtr = infoPtr->nextPtr;
+    ckfree((char*)infoPtr);
+
+    return result;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * Tcl_PidObjCmd --
+ *
+ *	This procedure is invoked to process the "pid" Tcl command.
+ *	See the user documentation for details on what it does.
+ *
+ * Results:
+ *	A standard Tcl result.
+ *
+ * Side effects:
+ *	See the user documentation.
+ *
+ *----------------------------------------------------------------------
+ */
+
+	/* ARGSUSED */
+int
+Tcl_PidObjCmd(dummy, interp, objc, objv)
+    ClientData dummy;		/* Not used. */
+    Tcl_Interp *interp;		/* Current interpreter. */
+    int objc;			/* Number of arguments. */
+    Tcl_Obj *CONST *objv;	/* Argument strings. */
+{
+    Tcl_Channel chan;
+    Tcl_ChannelType *chanTypePtr;
+    PipeInfo *pipePtr;
+    int i;
+    Tcl_Obj *resultPtr;
+    char buf[20];
+
+    if (objc > 2) {
+	Tcl_WrongNumArgs(interp, 1, objv, "?channelId?");
+	return TCL_ERROR;
+    }
+    if (objc == 1) {
+	resultPtr = Tcl_GetObjResult(interp);
+	sprintf(buf, "%lu", (unsigned long) getpid());
+	Tcl_SetStringObj(resultPtr, buf, -1);
+    } else {
+        chan = Tcl_GetChannel(interp, Tcl_GetStringFromObj(objv[1], NULL),
+		NULL);
+        if (chan == (Tcl_Channel) NULL) {
+	    return TCL_ERROR;
+	}
+	chanTypePtr = Tcl_GetChannelType(chan);
+	if (chanTypePtr != &pipeChannelType) {
+	    return TCL_OK;
+	}
+
+        pipePtr = (PipeInfo *) Tcl_GetChannelInstanceData(chan);
+	resultPtr = Tcl_GetObjResult(interp);
+        for (i = 0; i < pipePtr->numPids; i++) {
+	    sprintf(buf, "%lu", TclpGetPid(pipePtr->pidPtr[i]));
+	    Tcl_ListObjAppendElement(/*interp*/ NULL, resultPtr,
+		    Tcl_NewStringObj(buf, -1));
+	}
+    }
+    return TCL_OK;
+}