ESMF_TraceRegionEnter Subroutine

  subroutine ESMF_TraceRegionEnter(name, rc)
! !ARGUMENTS: 
    character(len=*), intent(in) :: name
    integer, intent(out), optional  :: rc
!
! !DESCRIPTION:
!   Record an event in the trace for this PET indicating entry
!   into a user-defined region with the given name.  This call
!   must be paired with a call to {\tt ESMF\_TraceRegionExit()}
!   with a matching {\tt name} parameter.  User-defined regions may be
!   nested.
!   If tracing is disabled on the calling PET or for the application
!   as a whole, no event will be recorded and
!   the call will return immediately.
!
! The arguments are:
! \begin{description}
! \item[{name}]
!   A user-defined name for the region of code being entered
! \item[{[rc]}]
!   Return code; equals {\tt ESMF\_SUCCESS} if there are no errors.
! \end{description}    
!EOP
!-------------------------------------------------------------------------------
    if (present(rc)) rc = ESMF_SUCCESS 
    
    call c_esmftrace_region_enter(name, rc)
    if (ESMF_LogFoundError(rc, ESMF_ERR_PASSTHRU, &
         ESMF_CONTEXT, rcToReturn=rc)) return

  end subroutine ESMF_TraceRegionEnter