* traces, store the level at which the step
				 * trace was invoked */
    char *startCmd;		/* Used for bookkeeping with step execution
				 * traces, store the command name which
				 * invoked step trace */
    int curFlags;		/* Trace flags for the current command */
    int curCode;		/* Return code for the current command */
    Tcl_Size refCount;		/* Used to ensure this structure is not
				 * deleted too early. Keeps track of how many
				 * pieces of code have a pointer to this
				 * structure. */
    char command[TCLFLEXARRAY];	/* Space for Tcl command to invoke. Actual
				 * size will be as large as necessary to hold
				 * command. This field must be the last in the
				 * structure, so that it can be larger than 1

			    Tcl_Size objc, Tcl_Obj *const objv[]);
static char *		TraceVarProc(void *clientData, Tcl_Interp *interp,
			    const char *name1, const char *name2, int flags);
static void		TraceCommandProc(void *clientData,
			    Tcl_Interp *interp, const char *oldName,
			    const char *newName, int flags);
static Tcl_CmdObjTraceProc2 TraceExecutionProc;
#ifndef TCL_NO_DEPRECATED
static int		StringTraceProc(void *clientData,
			    Tcl_Interp *interp, Tcl_Size level,
			    const char *command, Tcl_Command commandInfo,
			    Tcl_Size objc, Tcl_Obj *const objv[]);
static void		StringTraceDeleteProc(void *clientData);
#endif /* TCL_NO_DEPRECATED */
static void		DisposeTraceResult(int flags, char *result);
static int		TraceVarEx(Tcl_Interp *interp, const char *part1,
			    const char *part2, VarTrace *tracePtr);

/*
 * The following structure holds the client data for string-based
 * trace procs
 */

#ifndef TCL_NO_DEPRECATED
typedef struct {
    void *clientData;		/* Client data from Tcl_CreateTrace */
    Tcl_CmdTraceProc *proc;	/* Trace function from Tcl_CreateTrace */
} StringTraceData;
#endif /* TCL_NO_DEPRECATED */

/*
 * Convenience macros for iterating over the list of traces. Note that each of
 * these *must* be treated as a command, and *must* have a block following it.
 */

#define FOREACH_VAR_TRACE(interp, name, clientData) \

 *----------------------------------------------------------------------
 */

int
Tcl_TraceObjCmd(
    TCL_UNUSED(void *),
    Tcl_Interp *interp,		/* Current interpreter. */
    Tcl_Size objc,			/* Number of arguments. */
    Tcl_Obj *const objv[])	/* Argument objects. */
{
    /* Main sub commands to 'trace' */
    static const char *const traceOptions[] = {
	"add", "info", "remove",
	NULL
    };

 *
 *	When the trace is deleted, the 'delProc' function will be invoked,
 *	passing it the original client data.
 *
 *----------------------------------------------------------------------
 */

#ifndef TCL_NO_DEPRECATED
typedef struct {
    Tcl_CmdObjTraceProc *proc;
    Tcl_CmdObjTraceDeleteProc *delProc;
    void *clientData;
} TraceWrapperInfo;

static int

    info->proc = proc;
    info->delProc = delProc;
    info->clientData = clientData;
    return Tcl_CreateObjTrace2(interp, level, flags,
	    (proc ? traceWrapperProc : NULL),
	    info, traceWrapperDelProc);
}
#endif /* TCL_NO_DEPRECATED */

Tcl_Trace
Tcl_CreateObjTrace2(
    Tcl_Interp *interp,		/* Tcl interpreter */
    Tcl_Size level,		/* Maximum nesting level */
    int flags,			/* Flags, see above */
    Tcl_CmdObjTraceProc2 *proc,	/* Trace callback */

 *	command and the ClientData value it will receive, and argc and argv
 *	give the arguments to the command, after any argument parsing and
 *	substitution. Proc does not return a value.
 *
 *----------------------------------------------------------------------
 */

#ifndef TCL_NO_DEPRECATED
Tcl_Trace
Tcl_CreateTrace(
    Tcl_Interp *interp,		/* Interpreter in which to create trace. */
    Tcl_Size level,		/* Only call proc for commands at nesting
				 * level<=argument level (1=>top level). */
    Tcl_CmdTraceProc *proc,	/* Function to call before executing each
				 * command. */

static void
StringTraceDeleteProc(
    void *clientData)
{
    Tcl_Free(clientData);
}
#endif /* TCL_NO_DEPRECATED */

/*
 *----------------------------------------------------------------------
 *
 * Tcl_DeleteTrace --
 *
 *	Remove a trace.