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

    (Default) Applies only to breakpoints set with the following
    qualifiers (that is, when an address expression is not explicitly
    specified):

       /BRANCH
       /CALL
       /INSTRUCTION
       /INSTRUCTION=(opcode[, . . . ]) (VAX only)
       /LINE
       /VECTOR_INSTRUCTION (VAX only)

    When used with those qualifiers, /INTO causes the debugger to
    break at the specified points within called routines (as well as
    within the routine in which execution is currently suspended).
    The /INTO qualifier is the default and is the opposite of /OVER.

    When using /INTO, you can further qualify the break action with
    /[NO]JSB, /[NO]SHARE, and /[NO]SYSTEM.