NAME

       Tcl_SaveResult,  Tcl_RestoreResult,  Tcl_DiscardResult - save and restore an interpreter's
       result

SYNOPSIS

       #include <tcl.h>

       Tcl_SaveResult(interp, statePtr)

       Tcl_RestoreResult(interp, statePtr)

       Tcl_DiscardResult(statePtr)

ARGUMENTS

       Tcl_Interp        *interp    (in)      Interpreter for which state should be saved.

       Tcl_SavedResult   *statePtr  (in)      Pointer to location where interpreter result should
                                              be saved or restored.
_________________________________________________________________

DESCRIPTION

       These  routines  allows a C procedure to take a snapshot of the current interpreter result
       so that it can be restored after a call to Tcl_Eval or some other  routine  that  modifies
       the  interpreter  result.  These routines are passed a pointer to a structure that is used
       to store enough information to restore the interpreter result state.  This  structure  can
       be  allocated on the stack of the calling procedure.  These routines do not save the state
       of any error information in the interpreter (e.g. the errorCode or errorInfo variables).

       Tcl_SaveResult moves the string and object results of interp into the  location  specified
       by  statePtr.   Tcl_SaveResult  clears  the result for interp and leaves the result in its
       normal empty initialized state.

       Tcl_RestoreResult moves the string and object results from statePtr back into interp.  Any
       result or error that was already in the interpreter will be cleared.  The statePtr is left
       in an uninitialized state and cannot be used until another call to Tcl_SaveResult.

       Tcl_DiscardResult releases the saved interpreter state  stored  at  statePtr.   The  state
       structure  is  left  in  an  uninitialized  state and cannot be used until another call to
       Tcl_SaveResult.

       Once Tcl_SaveResult is called to save the interpreter result, either Tcl_RestoreResult  or
       Tcl_DiscardResult must be called to properly clean up the memory associated with the saved
       state.

KEYWORDS

       result, state, interp