  TBK$SHOW_TRACEBACK? 
 The Question is:
 
an 7.2 ECO mentions the following:
 
o  V7.2 TRACE users who call TBK$SHOW_TRACEBACK
directly may get ACCVIOs.   Images Affected:  [SYSLIB]TRACE.EXE
 
Question,  this TBK$SHOW_TRACEBACK,  does it have
a  public/documented interface?
 
if  not,  perhaps a sly hint?  sounds like it could be handy,
if not for production use, but mundane development hacking.
 
thanks.
 
-ldb
 
 
 
 
 
 
 The Answer is:
 
  The OpenVMS Alpha traceback API is neither documented nor supported.
 
  As for a hint: Consider acquiring the source listings for details
  on calling traceback directly.  See the FAQ for the part numbers.
 
  Here is another hint: here is the declaration of the (undocumented
  and unsupported and subject to change without notice) OpenVMS Alpha
  traceback call from the OpenVMS Alpha V7.1 source listings:
 
TBK$SHOW_TRACEBACK( FAULTING_FP           : QUAD,
                    FAULTING_SP           : QUAD,
                    FAULTING_PC           : QUAD,
                    DETAIL_LEVEL          : LONG,
                    USER_ACTION_PROCEDURE : REF VECTOR[,LONG],
                    USER_ARG              : LONG)
 
! FUNCTION
!       This routine returns formatted information about the program call
!       stack and passes that information to the specified or default
!       action routine.  (For consistency, the arguments are modeled after
!       other LIB$SHOW* routines).
 
! INPUTS
!       FAULTING_FP -   The FP which identifies the invocation (i.e., frame)
!                       at which the traceback is to begin. For image activator-
!                       invoked traceback, this value is the FP at which the
!                       fault occured (which invokes traceback). For consumers
!                       of the callable interface, this is simply the current
!                       FP value (or the FP of an earlier invocation). The FP
!                       value must be consistent with the values in
!                       FAULTING_SP and FAULTING_PC.
 
!       FAULTING_SP -   The SP which identifies the invocation (i.e., frame)
!                       at which the traceback is to begin. For image activator-
!                       invoked traceback, this value is the SP at which the
!                       fault occured (which causes traceback to be invoked).
!                       For consumers of the callable interface, this is simply
!                       the current SP value (or the SP of an earlier
!                       invocation). The SP value must be consistent with the
!                       values in FAULTING_FP and FAULTING_PC.
 
!       FAULTING_PC -   The PC which identifies the invocation (i.e., frame)
!                       at which the traceback is to begin. For image activator-
!                       invoked traceback, this value is the PC at which the
!                       fault occured (which causes traceback to be invoked).
!                       For consumers of the callable interface, this is simply
!                       the current PC value (or the PC of an earlier
!                       invocation). The PC value must be consistent with the
!                       values in FAULTING_FP and FAULTING_SP.
 
!       DETAIL_LEVEL -  An identifier code specifying the level of detail
!                       required by the user.  The following are valid values
!                       for DETAIL_LEVEL. (CURRENTLY IGNORED)
 
!                           0 - nonsymbolic traceback, including header
 
!       USER_ACTION_PROCEDURE -
!                       Optional user-supplied action routine.  By default
!                       this routine prints traceback information to SYS$OUTPUT
!                       via LIB$PUT_OUTPUT.
 
!       USER_ARG -      Optional value to be passed directly to the action
!                       routine without interpretation.
 
 
