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

       /SHARE (default)
       /NOSHARE

    Qualifies a previous SET STEP INTO command or a current STEP/INTO
    command.

    If execution is currently suspended at a call to a shareable
    image routine, STEP/INTO/NOSHARE has the same effect as
    STEP/OVER. Otherwise, STEP/INTO/NOSHARE has the same effect as
    STEP/INTO.

    Use STEP/INTO/SHARE to override a previous SET STEP NOSHARE
    command. STEP/INTO/SHARE enables STEP/INTO to step into shareable
    image routines, as well as into other kinds of routines.