Library /sys$common/syshlp/dbg$help.hlb DEBUG, SET, WATCH, Qualifiers, /INTO  *Conan The Librarian (sorry for the slow response - running on an old VAX)

    Specifies that the debugger is to monitor a nonstatic variable
    by tracing instructions not only within the defining routine, but
    also within a routine that is called from the defining routine
    (and any other such nested calls). The SET WATCH/INTO command
    enables you to monitor nonstatic variables within called routines
    more precisely than SET WATCH/OVER; but the speed of execution
    within called routines is faster with SET WATCH/OVER.