/sys$common/syshlp/helplib.hlb DEBUG, Qualifiers, /RESUME  *Conan The Librarian (sorry for the slow response - running on an old VAX)

       /RESUME (default)

    Reinvokes the non-kept debugger after a Ctrl/Y key sequence has
    interrupted the execution of a program you are debugging. (The
    interrupted program must not have been linked with a /NOTRACEBACK
    qualifier on the LINK command.)

    If you issue the DEBUG/RESUME command without a previous Ctrl/Y
    key sequence, no action occurs.