VMS Help System Services, $LKWSET  *Conan The Librarian (sorry for the slow response - running on an old VAX)

    Locks a range of pages in the working set; if the pages are not
    already in the working set, it brings them in and locks them. A
    page locked in the working set does not become a candidate for
    replacement.

    Format

      SYS$LKWSET  inadr ,[retadr] ,[acmode]

    C Prototype

      int sys$lkwset  ( struct _va_range *inadr, struct _va_range

                      *retadr, unsigned int acmode);

    Arguments

 inadr

    OpenVMS usage:address_range
    type:         longword (unsigned)
    access:       read only
    mechanism:    by reference
    Starting and ending virtual addresses of the range of pages to be
    locked in the working set. The inadr argument is the address of
    a 2-longword array containing, in order, the starting and ending
    process virtual addresses. Only the virtual page number portion
    of each virtual address is used; the low-order byte-within-page
    bits are ignored.

    On VAX systems, if the starting and ending virtual addresses are
    the same, a single page is locked.

 retadr

    OpenVMS usage:address_range
    type:         longword (unsigned)
    access:       write only
    mechanism:    by reference
    Starting and ending process virtual addresses of the range of
    pages actually locked by $LCKWSET. The retadr argument is the
    address of a 2-longword array containing, in order, the starting
    and ending process virtual addresses.

 acmode

    OpenVMS usage:access_mode
    type:         longword (unsigned)
    access:       read only
    mechanism:    by value
    Access mode to be associated with the pages to be locked. The
    acmode argument is a longword containing the access mode. The
    $PSLDEF macro defines the four access modes.

    The most privileged access mode used is the access mode of the
    caller. For the $LKWSET service to complete successfully, the
    resultant access mode must be equal to or more privileged than
    the access mode already associated with the pages to be locked.