Tcl Source Code

1999-04-02    <[email protected]>

	* doc/dde.n:
	* tools/tcl.wse.in:
	* win/makefile.vc:
	* win/pkgIndex.tcl:
	* win/tclWinDde.c:  Add new DDE package, code removed from Tk now
	separated into its own package.  Changed DDE-based send code into
	"dde eval" command.  Can be loaded into tclsh (not just wish).
	Windows only.

1999-04-02    <[email protected]>

	* tests/expr.test: 
	* tests/for-old.test: 
	* tests/for.test: 
	* tests/foreach.test: 
	* tests/format.test: 

'\"
'\" Copyright (c) 1997 Sun Microsystems, Inc.
'\"
'\" See the file "license.terms" for information on usage and redistribution
'\" of this file, and for a DISCLAIMER OF ALL WARRANTIES.
'\" 
'\" RCS: @(#) $Id: dde.n,v 1.1.2.1 1999/04/02 23:48:32 redman Exp $
'\" 
.so man.macros
.TH dde n 8.1 Tcl "Tcl Built-In Commands"
.BS
'\" Note:  do not modify the .SH NAME line immediately below!
.SH NAME
dde \- Execute a Dynamic Data Exchange command
.SH SYNOPSIS
.sp
\fBpackage require dde 1.0\fR
.sp
\fBdde \fIservername \fR?\fItopic\fR?
.sp
\fBdde ?\-async?\fR \fIcommand service topic \fR?\fIdata\fR?
.BE

.SH DESCRIPTION
.PP
This command allows an application to send Dynamic Data Exchange (DDE)
command when running under Microsoft Windows. Dynamic Data Exchange is
a mechanism where applications can exchange raw data. Each DDE
transaction needs a \fIservice name\fR and a \fItopic\fR. Both the
\fIservice name\fR and \fItopic\fR are application defined; Tcl uses
the service name \fBTclEval\fR, while the topic name is the name of the
interpreter given by \fBdde servername\fR. Other applications have their
own \fIservice names\fR and \fItopics\fR. For instance, Microsoft Excel
has the service name \fBExcel\fR.
.PP
The only option to the \fBdde\fR command is:
.TP
\fB\-async\fR
Requests asynchronous invocation.  This is valid only for the
\fBexecute\fR subcommand. Normally, the \fBdde execute\fR subcommand
waits until the command completes, returning appropriate error
messages. When the \fB\-async\fR option is used, the command returns
immediately, and no error information is available.
.SH "DDE COMMANDS"
.PP
The following commands are a subset of the full Dynamic Data Exchange
set of commands.
.TP
\fBdde servername \fR?\fItopic\fR?
\fBdde servername\fR registers the interpreter as a DDE server with
the service name TclEval and the topic name specified byt \fItopic\fR.
If no \fItopic\fR is given, \fBdde servername\fR returns the name
of the current topic or the empty string if it is not registered as a service.
.TP
\fBdde execute \fIservice topic data\fR
\fBdde execute\fR takes the \fIdata\fR and sends it to the server
indicated by \fIservice\fR with the topic indicated by
\fItopic\fR. Typically, \fIservice\fR is the name of an application,
and \fItopic\fR is a file to work on.  The \fIdata\fR field is given
to the remote application. Typically, the application treats the
\fIdata\fR field as a script, and the script is run in the
application. The command returns an error if the script did not
run. If the \fB\-async\fR flag was used, the command
returns immediately with no error.
.TP
\fBdde request \fIservice topic item\fR
\fBdde request\fR is typically used to get the value of something; the
value of a cell in Microsoft Excel or the text of a selection in
Microsoft Word. \fIservice\fR is typically the name of an application,
\fItopic\fR is typically the name of the file, and \fIitem\fR is
application-specific. The command returns the value of \fIitem\fR as
defined in the application.
.TP
\fBdde services \fIservice topic\fR
\fBdde services\fR returns a list of service-topic pairs that
currently exist on the machine. If \fIservice\fR and \fItopic\fR are
both null strings ({}), then all service-topic pairs currently
available on the system are returned. If \fIservice\fR is null and
\fItopic\fR is not, then all services with the specified topic are
returned. If \fIservice\fR is not null and \fItopic\fR is, all topics
for a given service are returned. If both are not null, if that
service-topic pair currently exists, it is returned; otherwise, null
is returned.
.TP
\fBdde eval \fItopic cmd \fR?\fIarg arg ...\fR?
\fBdde eval\fR evaluates a command and its arguments using the
interpreter specified by \fItopic\fR. The DDE service must be the
"TclEval" service.  This command can be used to replace send on Windows.
.SH "DDE AND TCL"
A Tcl interpreter always has a service name of "TclEval". Each
different interp of all running Tcl applications should a unique
name specified by \fBdde servername\fR. Each interp is available as a
DDE topic only if the \fBdde servername\fR command was used to set the
name of the topic for each interp. So a \fBdde services TclEval {}\fR
command will return a list of service-topic pairs, where each of the
currently running interps will be a topic.
.PP
When Tcl processes a \fBdde execute\fR command, the data for the
execute is run as a script in the interp named by the topic of the
\fBdde execute\fR command.
.PP
When Tcl processes a \fBdde request\fR command, it returns the value of
the variable given in the dde command in the context of the interp
named by the dde topic. Tcl reserves the variable "$TCLEVAL$EXECUTE$RESULT"
for internal use, and \fBdde request\fR commands for that variable
will give unpredictable results.
.PP
An external application which wishes to run a script in Tcl should have
that script store its result in a variable, run the \fBdde execute\fR
command, and the run \fBdde request\fR to get the value of the
variable.
.PP
When using DDE, be careful to ensure that the event queue is flushed
using either \fBupdate\fR or \fBvwait\fR.  This happens by default
when using \fBwish\fR unless a blocking command is called (such as \fBexec\fR
without adding the \fB&\fR to place the process in the background).
If for any reason the event queue is not flushed, DDE commands may
hang until the event queue is flushed.  This can create a deadlock
situation.
.SH KEYWORDS
application, dde, name, remote execution
.SH "SEE ALSO"
tk, winfo, send

  Flags=0000000000000010
end
item: Install File
  Source=${__TCLBASEDIR__}\win\release\tclreg81.dll
  Destination=%MAINDIR%\lib\tcl%VER%\reg1.0\tclreg81.dll
  Flags=0000000000000010
end
item: Install File
  Source=${__TCLBASEDIR__}\win\pkgIndex.tcl
  Destination=%MAINDIR%\lib\tcl%VER%\dde1.0\pkgIndex.tcl
  Flags=0000000000000010
end
item: Install File
  Source=${__TCLBASEDIR__}\win\release\tcldde81.dll
  Destination=%MAINDIR%\lib\tcl%VER%\dde1.0\tcldde81.dll
  Flags=0000000000000010
end
item: Install File
  Source=C:\WINNT\SYSTEM32\Msvcrt.dll
  Destination=%MAINDIR%\bin\msvcrt.dll
  Flags=0010001000000011
end
item: Install File
  Source=${__TKBASEDIR__}\win\release\wish81.exe

# Visual C++ 2.x and 4.0 makefile
#
# See the file "license.terms" for information on usage and redistribution
# of this file, and for a DISCLAIMER OF ALL WARRANTIES.
# 
# Copyright (c) 1995-1996 Sun Microsystems, Inc.
# Copyright (c) 1998-1999 by Scriptics Corporation.
#
# RCS: @(#) $Id: makefile.vc,v 1.1.2.23 1999/04/02 23:48:33 redman Exp $

# Does not depend on the presence of any environment variables in
# order to compile tcl; all needed information is derived from 
# location of the compiler directories.

#
# Project directories

TCL16DLL	= $(OUTDIR)\$(NAMEPREFIX)16$(VERSION)$(DBGX).dll
TCLSH		= $(OUTDIR)\$(NAMEPREFIX)sh$(VERSION)$(DBGX).exe
TCLSHP		= $(OUTDIR)\$(NAMEPREFIX)shp$(VERSION)$(DBGX).exe
TCLPIPEDLLNAME	= $(NAMEPREFIX)pip$(VERSION)$(DBGX).dll
TCLPIPEDLL	= $(OUTDIR)\$(TCLPIPEDLLNAME)
TCLREGDLLNAME	= $(NAMEPREFIX)reg$(VERSION)$(DBGX).dll
TCLREGDLL	= $(OUTDIR)\$(TCLREGDLLNAME)
TCLDDEDLLNAME	= $(NAMEPREFIX)dde$(VERSION)$(DBGX).dll
TCLDDEDLL	= $(OUTDIR)\$(TCLDDEDLLNAME)
TCLTEST		= $(OUTDIR)\$(NAMEPREFIX)test.exe
DUMPEXTS	= $(TMPDIR)\dumpexts.exe
CAT16		= $(TMPDIR)\cat16.exe
CAT32		= $(TMPDIR)\cat32.exe
RMDIR		= .\rmd.bat
MKDIR		= .\mkd.bat
RM		= del

!ENDIF

######################################################################
# Project specific targets
######################################################################

release:    setup $(TCLSH) dlls
dlls:	    setup $(TCL16DLL) $(TCLPIPEDLL) $(TCLREGDLL) $(TCLDDEDLL)
all:	    setup $(TCLSH) dlls $(CAT16) $(CAT32) 
tcltest:    setup $(TCLTEST) dlls $(CAT16) $(CAT32)
plugin:	    setup $(TCLPLUGINDLL) $(TCLSHP)
install:    install-binaries install-libraries
test:	    setup $(TCLTEST) dlls $(CAT16) $(CAT32)
	copy $(WINDIR)\pkgIndex.tcl $(OUTDIR)
	set TCL_LIBRARY=$(ROOT)/library

<<
	if exist $(cc16) $(rc16) -i $(GENERICDIR) $(TCL_DEFINES) $(WINDIR)\tcl16.rc $@

$(TCLPIPEDLL): $(WINDIR)\stub16.c
	$(cc32) $(CON_CFLAGS) -Fo$(TMPDIR)\ $(WINDIR)\stub16.c
	set LIB="$(TOOLS32)\lib"
	$(link32) $(ldebug) $(conlflags) -out:$@ $(TMPDIR)\stub16.obj $(guilibs)

$(TCLDDEDLL): $(TMPDIR)\tclWinDde.obj $(TCLSTUBLIB)
	set LIB="$(TOOLS32)\lib"
	$(link32) $(ldebug) $(dlllflags) -out:$@ $(TMPDIR)\tclWinDde.obj \
		$(conlibsdll) $(TCLSTUBLIB)

$(TCLREGDLL): $(TMPDIR)\tclWinReg.obj $(TCLSTUBLIB)
	set LIB="$(TOOLS32)\lib"
	$(link32) $(ldebug) $(dlllflags) -out:$@ $(TMPDIR)\tclWinReg.obj \
		$(conlibsdll) $(TCLSTUBLIB)

$(CAT32): $(WINDIR)\cat.c

	@copy "$(TCLLIB)" "$(LIB_INSTALL_DIR)"
	@echo installing "$(TCLSH)"
	@copy "$(TCLSH)" "$(BIN_INSTALL_DIR)"
	@echo installing $(TCLPIPEDLLNAME)
	@copy "$(TCLPIPEDLL)" "$(BIN_INSTALL_DIR)"
	@echo installing $(TCLREGDLLNAME)
	@copy "$(TCLREGDLL)" "$(LIB_INSTALL_DIR)"
	@echo installing $(TCLDDEDLLNAME)
	@copy "$(TCLDDEDLL)" "$(LIB_INSTALL_DIR)"
	@echo installing $(TCLSTUBLIBNAME)
	@copy "$(TCLSTUBLIB)" "$(LIB_INSTALL_DIR)"

install-libraries:
	-@$(MKDIR) "$(LIB_INSTALL_DIR)"
	-@$(MKDIR) "$(INCLUDE_INSTALL_DIR)"
	-@$(MKDIR) "$(SCRIPT_INSTALL_DIR)"
	-@$(MKDIR) "$(SCRIPT_INSTALL_DIR)\http1.0"
	@copy << "$(SCRIPT_INSTALL_DIR)\pkgIndex.tcl"
package ifneeded registry 1.0 "load [list [file join $$dir .. $(TCLREGDLLNAME)]] registry"
package ifneeded dde 1.0 "load [list [file join $$dir .. $(TCLDDEDLLNAME)]] dde"
<<
	-@copy "$(ROOT)\library\http1.0\http.tcl"     "$(SCRIPT_INSTALL_DIR)\http1.0"
	-@copy "$(ROOT)\library\http1.0\pkgIndex.tcl" "$(SCRIPT_INSTALL_DIR)\http1.0"
	-@$(MKDIR) "$(SCRIPT_INSTALL_DIR)\http2.0"
	-@copy "$(ROOT)\library\http2.0\http.tcl"     "$(SCRIPT_INSTALL_DIR)\http2.0"
	-@copy "$(ROOT)\library\http2.0\pkgIndex.tcl" "$(SCRIPT_INSTALL_DIR)\http2.0"
	-@$(MKDIR) "$(SCRIPT_INSTALL_DIR)\opt0.4"
	-@copy "$(ROOT)\library\opt0.4\optparse.tcl" "$(SCRIPT_INSTALL_DIR)\opt0.4"
	-@copy "$(ROOT)\library\opt0.4\pkgIndex.tcl" "$(SCRIPT_INSTALL_DIR)\opt0.4"
	-@copy "$(GENERICDIR)\tcl.h"         "$(INCLUDE_INSTALL_DIR)"
	-@copy "$(ROOT)\library\history.tcl" "$(SCRIPT_INSTALL_DIR)"
	-@copy "$(ROOT)\library\init.tcl"    "$(SCRIPT_INSTALL_DIR)"
	-@copy "$(ROOT)\library\ldAout.tcl"  "$(SCRIPT_INSTALL_DIR)"
	-@copy "$(ROOT)\library\parray.tcl"  "$(SCRIPT_INSTALL_DIR)"
	-@copy "$(ROOT)\library\safe.tcl"    "$(SCRIPT_INSTALL_DIR)"
	-@copy "$(ROOT)\library\tclIndex"    "$(SCRIPT_INSTALL_DIR)"
	-@copy "$(ROOT)\library\package.tcl" "$(SCRIPT_INSTALL_DIR)"
	-@copy "$(ROOT)\library\word.tcl"    "$(SCRIPT_INSTALL_DIR)"
	-@copy "$(ROOT)\library\auto.tcl"    "$(SCRIPT_INSTALL_DIR)"

#
# Regenerate the stubs files.
#

$(TMPDIR)\tclAppInit.obj : $(WINDIR)\tclAppInit.c
	$(cc32) $(TCL_CFLAGS) -Fo$@ $?

# The following objects should be built using the stub interfaces

$(TMPDIR)\tclWinReg.obj : $(WINDIR)\tclWinReg.c
	$(cc32) $(TCL_CFLAGS) -DUSE_TCL_STUBS -Fo$@ $?

$(TMPDIR)\tclWinDde.obj : $(WINDIR)\tclWinDde.c
	$(cc32) $(TCL_CFLAGS) -DUSE_TCL_STUBS -Fo$@ $?

# The following objects are part of the stub library and should not
# be built as DLL objects but none of the symbols should be exported

$(TMPDIR)\tclStubLib.obj : $(GENERICDIR)\tclStubLib.c
	$(cc32) $(TCL_CFLAGS) -DSTATIC_BUILD -Fo$@ $?

# Tcl package index file, version 1.0
# This file contains package information for Windows-specific extensions.
#
# Copyright (c) 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.
# 
# RCS: @(#) $Id: pkgIndex.tcl,v 1.1.2.3 1999/04/02 23:48:34 redman Exp $

package ifneeded registry 1.0 [list tclPkgSetup $dir registry 1.0 {{tclreg81.dll load registry}}]
package ifneeded dde 1.0 [list tclPkgSetup $dir dde 1.0 {{tcldde81.dll load dde}}]

/* 
 * tclWinDde.c --
 *
 *	This file provides procedures that implement the "send"
 *	command, allowing commands to be passed from interpreter
 *	to interpreter.
 *
 * Copyright (c) 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.
 *
 * RCS: @(#) $Id: tclWinDde.c,v 1.1.2.1 1999/04/02 23:48:34 redman Exp $
 */

#include "tclPort.h"
#include <ddeml.h>

/*
 * TCL_STORAGE_CLASS is set unconditionally to DLLEXPORT because the
 * Registry_Init declaration is in the source file itself, which is only
 * accessed when we are building a library.
 */

#undef TCL_STORAGE_CLASS
#define TCL_STORAGE_CLASS DLLEXPORT

/* 
 * The following structure is used to keep track of the interpreters
 * registered by this process.
 */

typedef struct RegisteredInterp {
    struct RegisteredInterp *nextPtr;
				/* The next interp this application knows
				 * about. */
    char *name;			/* Interpreter's name (malloc-ed). */
    Tcl_Interp *interp;		/* The interpreter attached to this name. */
} RegisteredInterp;

/*
 * Used to keep track of conversations.
 */

typedef struct Conversation {
    struct Conversation *nextPtr;
				/* The next conversation in the list. */
    RegisteredInterp *riPtr;	/* The info we know about the conversation. */
    HCONV hConv;		/* The DDE handle for this conversation. */
    Tcl_Obj *returnPackagePtr;	/* The result package for this conversation. */
} Conversation;

typedef struct ThreadSpecificData {
    Conversation *currentConversations;
                                /* A list of conversations currently
				 * being processed. */
    RegisteredInterp *interpListPtr;
                                /* List of all interpreters registered
				 * in the current process. */
} ThreadSpecificData;
static Tcl_ThreadDataKey dataKey;

/*
 * The following variables cannot be placed in thread-local storage.
 * The Mutex ddeMutex guards access to the ddeInstance.
 */
static DWORD ddeInstance;       /* The application instance handle given
				 * to us by DdeInitialize. */
static int ddeIsServer = 0;

TCL_DECLARE_MUTEX(ddeMutex)

/*
 * Forward declarations for procedures defined later in this file.
 */

static void		    DdeExitProc _ANSI_ARGS_((ClientData clientData));
static void		    DeleteProc _ANSI_ARGS_((ClientData clientData));
static Tcl_Obj *	    ExecuteRemoteObject _ANSI_ARGS_((
				RegisteredInterp *riPtr, 
				Tcl_Obj *ddeObjectPtr));
static int		    MakeDdeConnection _ANSI_ARGS_((Tcl_Interp *interp,
				char *name, HCONV *ddeConvPtr));
static HDDEDATA CALLBACK    DdeServerProc _ANSI_ARGS_((UINT uType,
				UINT uFmt, HCONV hConv, HSZ ddeTopic,
				HSZ ddeItem, HDDEDATA hData, DWORD dwData1, 
				DWORD dwData2));
static void		    SetDdeError _ANSI_ARGS_((Tcl_Interp *interp));
int Tcl_DdeObjCmd(ClientData clientData,	/* Used only for deletion */
	Tcl_Interp *interp,		/* The interp we are sending from */
	int objc,			/* Number of arguments */
	Tcl_Obj *CONST objv[]);	/* The arguments */

EXTERN int Dde_Init(Tcl_Interp *interp);

/*
 *----------------------------------------------------------------------
 *
 * Dde_Init --
 *
 *	This procedure initializes the dde command.
 *
 * Results:
 *	A standard Tcl result.
 *
 * Side effects:
 *	None.
 *
 *----------------------------------------------------------------------
 */

int
Dde_Init(
    Tcl_Interp *interp)
{
    ThreadSpecificData *tsdPtr;
    
    if (!Tcl_InitStubs(interp, "8.0", 0)) {
	return TCL_ERROR;
    }

    Tcl_CreateObjCommand(interp, "dde", Tcl_DdeObjCmd, NULL, NULL);

    tsdPtr = (ThreadSpecificData *)
	Tcl_GetThreadData((Tcl_ThreadDataKey *) &dataKey, sizeof(ThreadSpecificData));
    
    if (tsdPtr == NULL) {
	tsdPtr = TCL_TSD_INIT(&dataKey);
	tsdPtr->currentConversations = NULL;
	tsdPtr->interpListPtr = NULL;
    }
    Tcl_CreateExitHandler(DdeExitProc, NULL);

    return Tcl_PkgProvide(interp, "dde", "1.0");
}



static void
Initialize()
{
    int nameFound = 0;
    HSZ ddeService = 0;
    ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);
    
    /*
     * See if the application is already registered; if so, remove its
     * current name from the registry. The deletion of the command
     * will take care of disposing of this entry.
     */

    if (tsdPtr->interpListPtr != NULL) {
	nameFound = 1;
    }

    /*
     * First, if Dde has been initialized as a client, uninitialize it.
     */
    if ((ddeInstance != 0) && (ddeIsServer == 0) && (nameFound != 0)) {
	Tcl_MutexLock(&ddeMutex);
	DdeUninitialize(ddeInstance);
	ddeInstance = 0;
    }

	
    /*
     * Make sure that the DDE server is there. This is done only once,
     * add an exit handler tear it down.
     */

    if (ddeInstance == 0) {
	Tcl_MutexLock(&ddeMutex);
	if (ddeInstance == 0) {
	    if (nameFound != 0) {
		if (DdeInitialize(&ddeInstance, DdeServerProc,
			CBF_SKIP_REGISTRATIONS
			| CBF_SKIP_UNREGISTRATIONS
			| CBF_FAIL_POKES, 0) 
			!= DMLERR_NO_ERROR) {
		    DdeUninitialize(ddeInstance);
		    ddeInstance = 0;
		} else {
		    ddeIsServer = 1;
		    Tcl_CreateExitHandler(DdeExitProc, NULL);
		    ddeService = DdeCreateStringHandle(ddeInstance, "TclEval", 0);
		    DdeNameService(ddeInstance, ddeService, 0L, DNS_REGISTER);
		}
	    } else {
		if (DdeInitialize(&ddeInstance, NULL,
			CBF_SKIP_REGISTRATIONS
			| CBF_SKIP_UNREGISTRATIONS
			| CBF_FAIL_POKES
			| APPCMD_CLIENTONLY
			| APPCMD_FILTERINITS, 0) 
			!= DMLERR_NO_ERROR) {
		    DdeUninitialize(ddeInstance);
		    ddeInstance = 0;
		} else {
		    ddeIsServer = 0;
		}
	    }
	}
	Tcl_MutexUnlock(&ddeMutex);
    }
}    


/*
 *--------------------------------------------------------------
 *
 * DdeSetServerName --
 *
 *	This procedure is called to associate an ASCII name with a Dde
 *	server.  If the interpreter has already been named, the
 *	name replaces the old one.
 *
 * Results:
 *	The return value is the name actually given to the interp.
 *	This will normally be the same as name, but if name was already
 *	in use for a Dde Server then a name of the form "name #2" will
 *	be chosen,  with a high enough number to make the name unique.
 *
 * Side effects:
 *	Registration info is saved, thereby allowing the "send" command
 *	to be used later to invoke commands in the application.  In
 *	addition, the "send" command is created in the application's
 *	interpreter.  The registration will be removed automatically
 *	if the interpreter is deleted or the "send" command is removed.
 *
 *--------------------------------------------------------------
 */

static char *
DdeSetServerName(interp, name)
    Tcl_Interp *interp;
    char *name;			/* The name that will be used to
				 * refer to the interpreter in later
				 * "send" commands.  Must be globally
				 * unique. */
{
    int suffix, offset;
    RegisteredInterp *riPtr, *prevPtr;
    Tcl_DString dString;
    ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);

    /*
     * See if the application is already registered; if so, remove its
     * current name from the registry. The deletion of the command
     * will take care of disposing of this entry.
     */

    for (riPtr = tsdPtr->interpListPtr, prevPtr = NULL; riPtr != NULL; 
	    prevPtr = riPtr, riPtr = riPtr->nextPtr) {
	if (riPtr->interp == interp) {
	    if (name != NULL) {
		if (prevPtr == NULL) {
		    tsdPtr->interpListPtr = tsdPtr->interpListPtr->nextPtr;
		} else {
		    prevPtr->nextPtr = riPtr->nextPtr;
		}
		break;
	    } else {
		/*
		 * the name was NULL, so the caller is asking for
		 * the name of the current interp.
		 */

		return riPtr->name;
	    }
	}
    }

    if (name == NULL) {
	/*
	 * the name was NULL, so the caller is asking for
	 * the name of the current interp, but it doesn't
	 * have a name.
	 */

	return "";
    }
    
    /*
     * Pick a name to use for the application.  Use "name" if it's not
     * already in use.  Otherwise add a suffix such as " #2", trying
     * larger and larger numbers until we eventually find one that is
     * unique.
     */

    suffix = 1;
    offset = 0;
    Tcl_DStringInit(&dString);

    /*
     * We have found a unique name. Now add it to the registry.
     */

    riPtr = (RegisteredInterp *) ckalloc(sizeof(RegisteredInterp));
    riPtr->interp = interp;
    riPtr->name = ckalloc(strlen(name) + 1);
    riPtr->nextPtr = tsdPtr->interpListPtr;
    tsdPtr->interpListPtr = riPtr;
    strcpy(riPtr->name, name);

    Tcl_CreateObjCommand(interp, "dde", Tcl_DdeObjCmd,
	    (ClientData) riPtr, DeleteProc);
    if (Tcl_IsSafe(interp)) {
	Tcl_HideCommand(interp, "dde", "dde");
    }
    Tcl_DStringFree(&dString);

    return riPtr->name;
}

/*
 *--------------------------------------------------------------
 *
 * DeleteProc
 *
 *	This procedure is called when the command "dde" is destroyed.
 *
 * Results:
 *	none
 *
 * Side effects:
 *	The interpreter given by riPtr is unregistered.
 *
 *--------------------------------------------------------------
 */

static void
DeleteProc(clientData)
    ClientData clientData;	/* The interp we are deleting passed
				 * as ClientData. */
{
    RegisteredInterp *riPtr = (RegisteredInterp *) clientData;
    RegisteredInterp *searchPtr, *prevPtr;
    ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);

    for (searchPtr = tsdPtr->interpListPtr, prevPtr = NULL;
	    (searchPtr != NULL) && (searchPtr != riPtr);
	    prevPtr = searchPtr, searchPtr = searchPtr->nextPtr) {
	/*
	 * Empty loop body.
	 */
    }

    if (searchPtr != NULL) {
	if (prevPtr == NULL) {
	    tsdPtr->interpListPtr = tsdPtr->interpListPtr->nextPtr;
	} else {
	    prevPtr->nextPtr = searchPtr->nextPtr;
	}
    }
    ckfree(riPtr->name);
    Tcl_EventuallyFree(clientData, TCL_DYNAMIC);
}

/*
 *--------------------------------------------------------------
 *
 * ExecuteRemoteObject --
 *
 *	Takes the package delivered by DDE and executes it in
 *	the server's interpreter.
 *
 * Results:
 *	A list Tcl_Obj * that describes what happened. The first
 *	element is the numerical return code (TCL_ERROR, etc.).
 *	The second element is the result of the script. If the
 *	return result was TCL_ERROR, then the third element
 *	will be the value of the global "errorCode", and the
 *	fourth will be the value of the global "errorInfo".
 *	The return result will have a refCount of 0.
 *
 * Side effects:
 *	A Tcl script is run, which can cause all kinds of other
 *	things to happen.
 *
 *--------------------------------------------------------------
 */

static Tcl_Obj *
ExecuteRemoteObject(
    RegisteredInterp *riPtr,	    /* Info about this server. */
    Tcl_Obj *ddeObjectPtr)	    /* The object to execute. */
{
    Tcl_Obj *errorObjPtr;
    Tcl_Obj *returnPackagePtr;
    int result;

    result = Tcl_EvalObjEx(riPtr->interp, ddeObjectPtr, TCL_EVAL_GLOBAL);
    returnPackagePtr = Tcl_NewListObj(0, (Tcl_Obj **) NULL);
    Tcl_ListObjAppendElement(NULL, returnPackagePtr,
	    Tcl_NewIntObj(result));
    Tcl_ListObjAppendElement(NULL, returnPackagePtr,
	    Tcl_GetObjResult(riPtr->interp));
    if (result == TCL_ERROR) {
	errorObjPtr = Tcl_GetVar2Ex(riPtr->interp, "errorCode", NULL,
		TCL_GLOBAL_ONLY);
	Tcl_ListObjAppendElement(NULL, returnPackagePtr, errorObjPtr);
	errorObjPtr = Tcl_GetVar2Ex(riPtr->interp, "errorInfo", NULL,
		TCL_GLOBAL_ONLY);
        Tcl_ListObjAppendElement(NULL, returnPackagePtr, errorObjPtr);
    }

    return returnPackagePtr;
}

/*
 *--------------------------------------------------------------
 *
 * DdeServerProc --
 *
 *	Handles all transactions for this server. Can handle
 *	execute, request, and connect protocols. Dde will
 *	call this routine when a client attempts to run a dde
 *	command using this server.
 *
 * Results:
 *	A DDE Handle with the result of the dde command.
 *
 * Side effects:
 *	Depending on which command is executed, arbitrary
 *	Tcl scripts can be run.
 *
 *--------------------------------------------------------------
 */

static HDDEDATA CALLBACK
DdeServerProc (
    UINT uType,			/* The type of DDE transaction we
				 * are performing. */
    UINT uFmt,			/* The format that data is sent or
				 * received. */
    HCONV hConv,		/* The conversation associated with the 
				 * current transaction. */
    HSZ ddeTopic,		/* A string handle. Transaction-type 
				 * dependent. */
    HSZ ddeItem,		/* A string handle. Transaction-type 
				 * dependent. */
    HDDEDATA hData,		/* DDE data. Transaction-type dependent. */
    DWORD dwData1,		/* Transaction-dependent data. */
    DWORD dwData2)		/* Transaction-dependent data. */
{
    Tcl_DString dString;
    int len;
    char *utilString;
    Tcl_Obj *ddeObjectPtr;
    HDDEDATA ddeReturn = NULL;
    RegisteredInterp *riPtr;
    Conversation *convPtr, *prevConvPtr;
    ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);

    switch(uType) {
	case XTYP_CONNECT:

	    /*
	     * Dde is trying to initialize a conversation with us. Check
	     * and make sure we have a valid topic.
	     */

	    len = DdeQueryString(ddeInstance, ddeTopic, NULL, 0, 0);
	    Tcl_DStringInit(&dString);
	    Tcl_DStringSetLength(&dString, len);
	    utilString = Tcl_DStringValue(&dString);
	    DdeQueryString(ddeInstance, ddeTopic, utilString, len + 1,
		    CP_WINANSI);

	    for (riPtr = tsdPtr->interpListPtr; riPtr != NULL;
		    riPtr = riPtr->nextPtr) {
		if (stricmp(utilString, riPtr->name) == 0) {
		    Tcl_DStringFree(&dString);
		    return (HDDEDATA) TRUE;
		}
	    }

	    Tcl_DStringFree(&dString);
	    return (HDDEDATA) FALSE;

	case XTYP_CONNECT_CONFIRM:

	    /*
	     * Dde has decided that we can connect, so it gives us a 
	     * conversation handle. We need to keep track of it
	     * so we know which execution result to return in an
	     * XTYP_REQUEST.
	     */

	    len = DdeQueryString(ddeInstance, ddeTopic, NULL, 0, 0);
	    Tcl_DStringInit(&dString);
	    Tcl_DStringSetLength(&dString, len);
	    utilString = Tcl_DStringValue(&dString);
	    DdeQueryString(ddeInstance, ddeTopic, utilString, len + 1, 
		    CP_WINANSI);
	    for (riPtr = tsdPtr->interpListPtr; riPtr != NULL; 
		    riPtr = riPtr->nextPtr) {
		if (stricmp(riPtr->name, utilString) == 0) {
		    convPtr = (Conversation *) ckalloc(sizeof(Conversation));
		    convPtr->nextPtr = tsdPtr->currentConversations;
		    convPtr->returnPackagePtr = NULL;
		    convPtr->hConv = hConv;
		    convPtr->riPtr = riPtr;
		    tsdPtr->currentConversations = convPtr;
		    break;
		}
	    }
	    Tcl_DStringFree(&dString);
	    return (HDDEDATA) TRUE;

	case XTYP_DISCONNECT:

	    /*
	     * The client has disconnected from our server. Forget this
	     * conversation.
	     */

	    for (convPtr = tsdPtr->currentConversations, prevConvPtr = NULL;
		    convPtr != NULL; 
		    prevConvPtr = convPtr, convPtr = convPtr->nextPtr) {
		if (hConv == convPtr->hConv) {
		    if (prevConvPtr == NULL) {
			tsdPtr->currentConversations = convPtr->nextPtr;
		    } else {
			prevConvPtr->nextPtr = convPtr->nextPtr;
		    }
		    if (convPtr->returnPackagePtr != NULL) {
			Tcl_DecrRefCount(convPtr->returnPackagePtr);
		    }
		    ckfree((char *) convPtr);
		    break;
		}
	    }
	    return (HDDEDATA) TRUE;

	case XTYP_REQUEST:

	    /*
	     * This could be either a request for a value of a Tcl variable,
	     * or it could be the send command requesting the results of the
	     * last execute.
	     */

	    if (uFmt != CF_TEXT) {
		return (HDDEDATA) FALSE;
	    }

	    ddeReturn = (HDDEDATA) FALSE;
	    for (convPtr = tsdPtr->currentConversations; (convPtr != NULL)
		    && (convPtr->hConv != hConv); convPtr = convPtr->nextPtr) {
		/*
		 * Empty loop body.
		 */
	    }

	    if (convPtr != NULL) {
		char *returnString;

		len = DdeQueryString(ddeInstance, ddeItem, NULL, 0,
			CP_WINANSI);
		Tcl_DStringInit(&dString);
		Tcl_DStringSetLength(&dString, len);
		utilString = Tcl_DStringValue(&dString);
		DdeQueryString(ddeInstance, ddeItem, utilString, 
                        len + 1, CP_WINANSI);
		if (stricmp(utilString, "$TCLEVAL$EXECUTE$RESULT") == 0) {
		    returnString =
		        Tcl_GetStringFromObj(convPtr->returnPackagePtr, &len);
		    ddeReturn = DdeCreateDataHandle(ddeInstance,
			    returnString, len+1, 0, ddeItem, CF_TEXT,
			    0);
		} else {
		    Tcl_Obj *variableObjPtr = Tcl_GetVar2Ex(
			    convPtr->riPtr->interp, utilString, NULL, 
			    TCL_GLOBAL_ONLY);
		    if (variableObjPtr != NULL) {
			returnString = Tcl_GetStringFromObj(variableObjPtr,
				&len);
			ddeReturn = DdeCreateDataHandle(ddeInstance,
				returnString, len+1, 0, ddeItem, CF_TEXT, 0);
		    } else {
			ddeReturn = NULL;
		    }
		}
		Tcl_DStringFree(&dString);
	    }
	    return ddeReturn;

	case XTYP_EXECUTE: {

	    /*
	     * Execute this script. The results will be saved into
	     * a list object which will be retreived later. See
	     * ExecuteRemoteObject.
	     */

	    Tcl_Obj *returnPackagePtr;

	    for (convPtr = tsdPtr->currentConversations; (convPtr != NULL)
		    && (convPtr->hConv != hConv); convPtr = convPtr->nextPtr) {
		/*
		 * Empty loop body.
		 */

	    }

	    if (convPtr == NULL) {
		return (HDDEDATA) DDE_FNOTPROCESSED;
	    }

	    utilString = (char *) DdeAccessData(hData, &len);
	    ddeObjectPtr = Tcl_NewStringObj(utilString, -1);
	    Tcl_IncrRefCount(ddeObjectPtr);
	    DdeUnaccessData(hData);
	    if (convPtr->returnPackagePtr != NULL) {
		Tcl_DecrRefCount(convPtr->returnPackagePtr);
	    }
	    convPtr->returnPackagePtr = NULL;
	    returnPackagePtr = 
		    ExecuteRemoteObject(convPtr->riPtr, ddeObjectPtr);
	    for (convPtr = tsdPtr->currentConversations; (convPtr != NULL)
 		    && (convPtr->hConv != hConv); convPtr = convPtr->nextPtr) {
		/*
		 * Empty loop body.
		 */

	    }
	    if (convPtr != NULL) {
		Tcl_IncrRefCount(returnPackagePtr);
		convPtr->returnPackagePtr = returnPackagePtr;
	    }
	    Tcl_DecrRefCount(ddeObjectPtr);
	    if (returnPackagePtr == NULL) {
		return (HDDEDATA) DDE_FNOTPROCESSED;
	    } else {
		return (HDDEDATA) DDE_FACK;
	    }
	}
	    
	case XTYP_WILDCONNECT: {

	    /*
	     * Dde wants a list of services and topics that we support.
	     */

	    HSZPAIR *returnPtr;
	    int i;
	    int numItems;

	    for (i = 0, riPtr = tsdPtr->interpListPtr; riPtr != NULL;
		    i++, riPtr = riPtr->nextPtr) {
		/*
		 * Empty loop body.
		 */

	    }

	    numItems = i;
	    ddeReturn = DdeCreateDataHandle(ddeInstance, NULL,
		    (numItems + 1) * sizeof(HSZPAIR), 0, 0, 0, 0);
	    returnPtr = (HSZPAIR *) DdeAccessData(ddeReturn, &len);
	    for (i = 0, riPtr = tsdPtr->interpListPtr; i < numItems; 
		    i++, riPtr = riPtr->nextPtr) {
		returnPtr[i].hszSvc = DdeCreateStringHandle(
                        ddeInstance, "TclEval", CP_WINANSI);
		returnPtr[i].hszTopic = DdeCreateStringHandle(
                        ddeInstance, riPtr->name, CP_WINANSI);
	    }
	    returnPtr[i].hszSvc = NULL;
	    returnPtr[i].hszTopic = NULL;
	    DdeUnaccessData(ddeReturn);
	    return ddeReturn;
	}

    }
    return NULL;
}


/*
 *--------------------------------------------------------------
 *
 * DdeExitProc --
 *
 *	Gets rid of our DDE server when we go away.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	The DDE server is deleted.
 *
 *--------------------------------------------------------------
 */

static void
DdeExitProc(
    ClientData clientData)	    /* Not used in this handler. */
{
    ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);

    DdeNameService(ddeInstance, NULL, 0, DNS_UNREGISTER);
    DdeUninitialize(ddeInstance);
    ddeInstance = 0;
}

/*
 *--------------------------------------------------------------
 *
 * MakeDdeConnection --
 *
 *	This procedure is a utility used to connect to a DDE
 *	server when given a server name and a topic name.
 *
 * Results:
 *	A standard Tcl result.
 *	
 *
 * Side effects:
 *	Passes back a conversation through ddeConvPtr
 *
 *--------------------------------------------------------------
 */

static int
MakeDdeConnection(
    Tcl_Interp *interp,		/* Used to report errors. */
    char *name,			/* The connection to use. */
    HCONV *ddeConvPtr)
{
    HSZ ddeTopic, ddeService;
    HCONV ddeConv;
    ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);
    
    ddeService = DdeCreateStringHandle(ddeInstance, "TclEval", 0);
    ddeTopic = DdeCreateStringHandle(ddeInstance, name, 0);

    ddeConv = DdeConnect(ddeInstance, ddeService, ddeTopic, NULL);
    DdeFreeStringHandle(ddeInstance, ddeService);
    DdeFreeStringHandle(ddeInstance, ddeTopic);

    if (ddeConv == (HCONV) NULL) {
	if (interp != NULL) {
	    Tcl_AppendResult(interp, "no registered server named \"",
		    name, "\"", (char *) NULL);
	}
	return TCL_ERROR;
    }

    *ddeConvPtr = ddeConv;
    return TCL_OK;
}

/*
 *--------------------------------------------------------------
 *
 * SetDdeError --
 *
 *	Sets the interp result to a cogent error message
 *	describing the last DDE error.
 *
 * Results:
 *	None.
 *	
 *
 * Side effects:
 *	The interp's result object is changed.
 *
 *--------------------------------------------------------------
 */

static void
SetDdeError(
    Tcl_Interp *interp)	    /* The interp to put the message in.*/
{
    Tcl_Obj *resultPtr = Tcl_GetObjResult(interp);
    int err;
    ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);

    err = DdeGetLastError(ddeInstance);
    switch (err) {
	case DMLERR_DATAACKTIMEOUT:
	case DMLERR_EXECACKTIMEOUT:
	case DMLERR_POKEACKTIMEOUT:
	    Tcl_SetStringObj(resultPtr,
		    "remote interpreter did not respond", -1);
	    break;

	case DMLERR_BUSY:
	    Tcl_SetStringObj(resultPtr, "remote server is busy", -1);
	    break;

	case DMLERR_NOTPROCESSED:
	    Tcl_SetStringObj(resultPtr, 
		    "remote server cannot handle this command", -1);
	    break;

	default:
	    Tcl_SetStringObj(resultPtr, "dde command failed", -1);
    }
}

/*
 *--------------------------------------------------------------
 *
 * Tcl_DdeObjCmd --
 *
 *	This procedure is invoked to process the "dde" Tcl command.
 *	See the user documentation for details on what it does.
 *
 * Results:
 *	A standard Tcl result.
 *
 * Side effects:
 *	See the user documentation.
 *
 *--------------------------------------------------------------
 */

int
Tcl_DdeObjCmd(
    ClientData clientData,	/* Used only for deletion */
    Tcl_Interp *interp,		/* The interp we are sending from */
    int objc,			/* Number of arguments */
    Tcl_Obj *CONST objv[])	/* The arguments */
{
    enum {
	DDE_SERVERNAME,
	DDE_EXECUTE,
	DDE_REQUEST,
	DDE_SERVICES,
	DDE_EVAL
    };

    static char *ddeCommands[] = {"servername", "execute",
          "request", "services", "eval", 
	  (char *) NULL};
    static char *ddeOptions[] = {"-async", (char *) NULL};
    int index, argIndex;
    int async = 0;
    int result = TCL_OK;
    HSZ ddeService = NULL;
    HSZ ddeTopic = NULL;
    HSZ ddeItem = NULL;
    HDDEDATA ddeData = NULL;
    HDDEDATA ddeItemData = NULL;
    HCONV hConv;
    HSZ ddeCookie = 0;
    char *serviceName, *topicName, *itemString, *dataString;
    char *string;
    int firstArg, length, dataLength;
    DWORD ddeResult;
    HDDEDATA ddeReturn;
    RegisteredInterp *riPtr;
    Tcl_Interp *sendInterp;
    Tcl_Obj *objPtr;
    ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);

    /*
     * Initialize DDE server/client
     */
    
    if (objc < 2) {
	Tcl_WrongNumArgs(interp, 1, objv, 
		"?-async? serviceName topicName value");
	return TCL_ERROR;
    }

    if (Tcl_GetIndexFromObj(interp, objv[1], ddeCommands, "command", 0,
	    &index) != TCL_OK) {
	return TCL_ERROR;
    }

    switch (index) {
	case DDE_SERVERNAME:
	    if ((objc != 3) && (objc != 2)) {
		Tcl_WrongNumArgs(interp, 1, objv, 
			"servername ?serverName?");
		return TCL_ERROR;
	    }
	    firstArg = (objc - 1);
	    break;
	case DDE_EXECUTE:
	    if ((objc < 5) || (objc > 6)) {
		Tcl_WrongNumArgs(interp, 1, objv, 
			"execute ?-async? serviceName topicName value");
		return TCL_ERROR;
	    }
	    if (Tcl_GetIndexFromObj(NULL, objv[2], ddeOptions, "option", 0,
		    &argIndex) != TCL_OK) {
		if (objc != 5) {
		    Tcl_WrongNumArgs(interp, 1, objv,
			    "execute ?-async? serviceName topicName value");
		    return TCL_ERROR;
		}
		async = 0;
		firstArg = 2;
	    } else {
		if (objc != 6) {
		    Tcl_WrongNumArgs(interp, 1, objv,
			    "execute ?-async? serviceName topicName value");
		    return TCL_ERROR;
		}
		async = 1;
		firstArg = 3;
	    }
	    break;
	case DDE_REQUEST:
	    if (objc != 5) {
		Tcl_WrongNumArgs(interp, 1, objv, 
			"request serviceName topicName value");
		return TCL_ERROR;
	    }
	    firstArg = 2;
	    break;
	case DDE_SERVICES:
	    if (objc != 4) {
		Tcl_WrongNumArgs(interp, 1, objv,
			"services serviceName topicName");
		return TCL_ERROR;
	    }
	    firstArg = 2;
	    break;
	case DDE_EVAL:
	    if (objc < 4) {
		Tcl_WrongNumArgs(interp, 1, objv, 
			"eval ?-async? serviceName args");
		return TCL_ERROR;
	    }
	    if (Tcl_GetIndexFromObj(NULL, objv[2], ddeOptions, "option", 0,
		    &argIndex) != TCL_OK) {
		if (objc < 4) {
		    Tcl_WrongNumArgs(interp, 1, objv,
			    "eval ?-async? serviceName args");
		    return TCL_ERROR;
		}
		async = 0;
		firstArg = 2;
	    } else {
		if (objc < 5) {
		    Tcl_WrongNumArgs(interp, 1, objv,
			    "eval ?-async? serviceName args");
		    return TCL_ERROR;
		}
		async = 1;
		firstArg = 3;
	    }
	    break;
    }

    if (firstArg != 1) {
	serviceName = Tcl_GetStringFromObj(objv[firstArg], &length);
    } else {
	serviceName = NULL;
    }

    if (length == 0) {
	serviceName = NULL;
    } else if (index != DDE_SERVERNAME) {
	ddeService = DdeCreateStringHandle(ddeInstance, serviceName,
		CP_WINANSI);
    }

    if ((index != DDE_SERVERNAME) &&(index != DDE_EVAL)) {
	topicName = Tcl_GetStringFromObj(objv[firstArg + 1], &length);
	if (length == 0) {
	    topicName = NULL;
	} else {
	    ddeTopic = DdeCreateStringHandle(ddeInstance, 
		    topicName, CP_WINANSI);
	}
    }

    switch (index) {
	case DDE_SERVERNAME: {
	    serviceName = DdeSetServerName(interp, serviceName);
	    if (serviceName != NULL) {
		Tcl_SetStringObj(Tcl_GetObjResult(interp),
			serviceName, -1);
		Initialize();
	    } else {
		Tcl_ResetResult(interp);
	    }
	    break;
	}
	case DDE_EXECUTE: {
	    Initialize();
	    dataString = Tcl_GetStringFromObj(objv[firstArg + 2], &dataLength);
	    if (dataLength == 0) {
		Tcl_SetStringObj(Tcl_GetObjResult(interp),
			"cannot execute null data", -1);
		result = TCL_ERROR;
		break;
	    }
	    hConv = DdeConnect(ddeInstance, ddeService, ddeTopic, 
                    NULL);

	    if (hConv == NULL) {
		SetDdeError(interp);
		result = TCL_ERROR;
		break;
	    }

	    ddeData = DdeCreateDataHandle(ddeInstance, dataString,
		    dataLength+1, 0, 0, CF_TEXT, 0);
	    if (ddeData != NULL) {
		if (async) {
		    DdeClientTransaction((LPBYTE) ddeData, 0xFFFFFFFF, hConv, 0, 
			    CF_TEXT, XTYP_EXECUTE, TIMEOUT_ASYNC, &ddeResult);
		    DdeAbandonTransaction(ddeInstance, hConv, 
                            ddeResult);
		} else {
		    ddeReturn = DdeClientTransaction((LPBYTE) ddeData, 0xFFFFFFFF,
			    hConv, 0, CF_TEXT, XTYP_EXECUTE, 7200000, NULL);
		    if (ddeReturn == 0) {
			SetDdeError(interp);
			result = TCL_ERROR;
		    }
		}
		DdeFreeDataHandle(ddeData);
	    } else {
		SetDdeError(interp);
		result = TCL_ERROR;
	    }
	    DdeDisconnect(hConv);
	    break;
	}
	case DDE_REQUEST: {
	    Initialize();
	    itemString = Tcl_GetStringFromObj(objv[firstArg + 2], &length);
	    if (length == 0) {
		Tcl_SetStringObj(Tcl_GetObjResult(interp),
			"cannot request value of null data", -1);
		return TCL_ERROR;
	    }
	    hConv = DdeConnect(ddeInstance, ddeService, ddeTopic, 
                    NULL);
	    
	    if (hConv == NULL) {
		SetDdeError(interp);
		result = TCL_ERROR;
	    } else {
		Tcl_Obj *returnObjPtr;
		ddeItem = DdeCreateStringHandle(ddeInstance, 
                        itemString, CP_WINANSI);
		if (ddeItem != NULL) {
		    ddeData = DdeClientTransaction(NULL, 0, hConv, ddeItem,
			    CF_TEXT, XTYP_REQUEST, 5000, NULL);
		    if (ddeData == NULL) {
			SetDdeError(interp);
			result = TCL_ERROR;
		    } else {
			dataString = DdeAccessData(ddeData, &dataLength);
			returnObjPtr = Tcl_NewStringObj(dataString, -1);
			DdeUnaccessData(ddeData);
			DdeFreeDataHandle(ddeData);
			Tcl_SetObjResult(interp, returnObjPtr);
		    }
		} else {
		    SetDdeError(interp);
		    result = TCL_ERROR;
		}
		DdeDisconnect(hConv);
	    }

	    break;
	}
	case DDE_SERVICES: {
	    HCONVLIST hConvList;
	    CONVINFO convInfo;
	    Tcl_Obj *convListObjPtr, *elementObjPtr;
	    Tcl_DString dString;
	    char *name;
	    
	    Initialize();
	    convInfo.cb = sizeof(CONVINFO);
	    hConvList = DdeConnectList(ddeInstance, ddeService, 
                    ddeTopic, 0, NULL);
	    hConv = 0;
	    convListObjPtr = Tcl_NewListObj(0, (Tcl_Obj **) NULL);
	    Tcl_DStringInit(&dString);

	    while (hConv = DdeQueryNextServer(hConvList, hConv), hConv != 0) {
		elementObjPtr = Tcl_NewListObj(0, (Tcl_Obj **) NULL);
		DdeQueryConvInfo(hConv, QID_SYNC, &convInfo);
		length = DdeQueryString(ddeInstance, 
                        convInfo.hszSvcPartner, NULL, 0, CP_WINANSI);
		Tcl_DStringSetLength(&dString, length);
		name = Tcl_DStringValue(&dString);
		DdeQueryString(ddeInstance, convInfo.hszSvcPartner, 
                        name, length + 1, CP_WINANSI);
		Tcl_ListObjAppendElement(interp, elementObjPtr,
			Tcl_NewStringObj(name, length));
		length = DdeQueryString(ddeInstance, convInfo.hszTopic,
			NULL, 0, CP_WINANSI);
		Tcl_DStringSetLength(&dString, length);
		name = Tcl_DStringValue(&dString);
		DdeQueryString(ddeInstance, convInfo.hszTopic, name,
			length + 1, CP_WINANSI);
		Tcl_ListObjAppendElement(interp, elementObjPtr,
			Tcl_NewStringObj(name, length));
		Tcl_ListObjAppendElement(interp, convListObjPtr, elementObjPtr);
	    }
	    DdeDisconnectList(hConvList);
	    Tcl_SetObjResult(interp, convListObjPtr);
	    Tcl_DStringFree(&dString);
	    break;
	}
	case DDE_EVAL: {
	    Initialize();
	    objc -= (async + 3);
	    ((Tcl_Obj **) objv) += (async + 3);

            /*
	     * See if the target interpreter is local.  If so, execute
	     * the command directly without going through the DDE server.
	     * Don't exchange objects between interps.  The target interp could
	     * compile an object, producing a bytecode structure that refers to 
	     * other objects owned by the target interp.  If the target interp 
	     * is then deleted, the bytecode structure would be referring to 
	     * deallocated objects.
	     */
	    
	    for (riPtr = tsdPtr->interpListPtr; riPtr != NULL; riPtr
		     = riPtr->nextPtr) {
		if (stricmp(serviceName, riPtr->name) == 0) {
		    break;
		}
	    }
	    
	    if (riPtr != NULL) {
		/*
		 * This command is to a local interp. No need to go through
		 * the server.
		 */
		
		Tcl_Preserve((ClientData) riPtr);
		sendInterp = riPtr->interp;
		Tcl_Preserve((ClientData) sendInterp);
		
		/*
		 * Don't exchange objects between interps.  The target interp would
		 * compile an object, producing a bytecode structure that refers to 
		 * other objects owned by the target interp.  If the target interp 
		 * is then deleted, the bytecode structure would be referring to 
		 * deallocated objects.
		 */

		if (objc == 1) {
		    result = Tcl_EvalObjEx(sendInterp, objv[0], TCL_EVAL_GLOBAL);
		} else {
		    objPtr = Tcl_ConcatObj(objc, objv);
		    Tcl_IncrRefCount(objPtr);
		    result = Tcl_EvalObjEx(sendInterp, objPtr, TCL_EVAL_GLOBAL);
		    Tcl_DecrRefCount(objPtr);
		}
		if (interp != sendInterp) {
		    if (result == TCL_ERROR) {
			/*
			 * An error occurred, so transfer error information from the
			 * destination interpreter back to our interpreter.  
			 */
			
			Tcl_ResetResult(interp);
			objPtr = Tcl_GetVar2Ex(sendInterp, "errorInfo", NULL, 
				TCL_GLOBAL_ONLY);
			string = Tcl_GetStringFromObj(objPtr, &length);
			Tcl_AddObjErrorInfo(interp, string, length);
			
			objPtr = Tcl_GetVar2Ex(sendInterp, "errorCode", NULL,
				TCL_GLOBAL_ONLY);
			Tcl_SetObjErrorCode(interp, objPtr);
		    }
		    Tcl_SetObjResult(interp, Tcl_GetObjResult(sendInterp));
		}
		Tcl_Release((ClientData) riPtr);
		Tcl_Release((ClientData) sendInterp);
	    } else {
		/*
		 * This is a non-local request. Send the script to the server and poll
		 * it for a result.
		 */
		
		if (MakeDdeConnection(interp, serviceName, &hConv) != TCL_OK) {
		    goto error;
		}
		
		objPtr = Tcl_ConcatObj(objc, objv);
		string = Tcl_GetStringFromObj(objPtr, &length);
		ddeItemData = DdeCreateDataHandle(ddeInstance, string, length+1, 0, 0,
			CF_TEXT, 0);
		
		if (async) {
		    ddeData = DdeClientTransaction((LPBYTE) ddeItemData, 0xFFFFFFFF, hConv, 0,
			    CF_TEXT, XTYP_EXECUTE, TIMEOUT_ASYNC, &ddeResult);
		    DdeAbandonTransaction(ddeInstance, hConv, ddeResult);
		} else {
		    ddeData = DdeClientTransaction((LPBYTE) ddeItemData, 0xFFFFFFFF, hConv, 0,
			    CF_TEXT, XTYP_EXECUTE, 7200000, NULL);
		    if (ddeData != 0) {
			
			ddeCookie = DdeCreateStringHandle(ddeInstance, 
				"$TCLEVAL$EXECUTE$RESULT", CP_WINANSI);
			ddeData = DdeClientTransaction(NULL, 0, hConv, ddeCookie,
				CF_TEXT, XTYP_REQUEST, 7200000, NULL);
		    }
		}
		
		
		Tcl_DecrRefCount(objPtr);
		
		if (ddeData == 0) {
		    SetDdeError(interp);
		    DdeFreeDataHandle(ddeItemData);
		    DdeDisconnect(hConv);
		    goto error;
		}
		
		if (async == 0) {
		    Tcl_Obj *resultPtr;
		    
		    /*
		     * The return handle has a two or four element list in it. The first
		     * element is the return code (TCL_OK, TCL_ERROR, etc.). The
		     * second is the result of the script. If the return code is TCL_ERROR,
		     * then the third element is the value of the variable "errorCode",
		     * and the fourth is the value of the variable "errorInfo".
		     */
		    
		    resultPtr = Tcl_NewObj();
		    length = DdeGetData(ddeData, NULL, 0, 0);
		    Tcl_SetObjLength(resultPtr, length);
		    string = Tcl_GetString(resultPtr);
		    DdeGetData(ddeData, string, length, 0);
		    Tcl_SetObjLength(resultPtr, strlen(string));
		    
		    if (Tcl_ListObjIndex(NULL, resultPtr, 0, &objPtr) != TCL_OK) {
			Tcl_DecrRefCount(resultPtr);
			goto error;
		    }
		    if (Tcl_GetIntFromObj(NULL, objPtr, &result) != TCL_OK) {
			Tcl_DecrRefCount(resultPtr);
			goto error;
		    }
		    if (result == TCL_ERROR) {
			Tcl_ResetResult(interp);
			
			if (Tcl_ListObjIndex(NULL, resultPtr, 3, &objPtr) != TCL_OK) {
			    Tcl_DecrRefCount(resultPtr);
			    goto error;
			}
			length = -1;
			string = Tcl_GetStringFromObj(objPtr, &length);
			Tcl_AddObjErrorInfo(interp, string, length);
			
			Tcl_ListObjIndex(NULL, resultPtr, 2, &objPtr);
			Tcl_SetObjErrorCode(interp, objPtr);
		    }
		    if (Tcl_ListObjIndex(NULL, resultPtr, 1, &objPtr) != TCL_OK) {
			Tcl_DecrRefCount(resultPtr);
			goto error;
		    }
		    Tcl_SetObjResult(interp, objPtr);
		    Tcl_DecrRefCount(resultPtr);
		}
	    }
	}
    }
    if (ddeCookie != NULL) {
	DdeFreeStringHandle(ddeInstance, ddeCookie);
    }
    if (ddeItem != NULL) {
	DdeFreeStringHandle(ddeInstance, ddeItem);
    }
    if (ddeItemData != NULL) {
	DdeFreeDataHandle(ddeItemData);
    }
    if (ddeData != NULL) {
	DdeFreeDataHandle(ddeData);
    }
    if (hConv != NULL) {
	DdeDisconnect(hConv);
    }
    return result;

    error:
    Tcl_SetStringObj(Tcl_GetObjResult(interp),
	    "invalid data returned from server", -1);
    if (ddeCookie != NULL) {
	DdeFreeStringHandle(ddeInstance, ddeCookie);
    }
    if (ddeItem != NULL) {
	DdeFreeStringHandle(ddeInstance, ddeItem);
    }
    if (ddeItemData != NULL) {
	DdeFreeDataHandle(ddeItemData);
    }
    if (ddeData != NULL) {
	DdeFreeDataHandle(ddeData);
    }
    if (hConv != NULL) {
	DdeDisconnect(hConv);
    }
    return TCL_ERROR;
}