region_id_64

    OpenVMS usage:region identifier
    type:         quadword (unsigned)
    access:       read only
    mechanism:    by 32- or 64-bit reference
    The region ID associated with the region to map the private page
    frame section. The file VADEF.H in SYS$STARLET_C.TLB and the
    $VADEF macro in STARLET.MLB define a symbolic name for each of
    the three default regions in P0, P1, and P2 space.

    The following region IDs are defined:

    Symbol     Region

    VA$C_P0    Program region
    VA$C_P1    Control region
    VA$C_P2    64-bit program region

    Other region IDs, as returned by the $CREATE_REGION_64 service,
    can be specified.

 start_pfn

    OpenVMS usage:page frame number
    type:         longword (unsigned)on Alpha, quadword (unsigned) on
                  Integrity servers
    access:       read only
    mechanism:    by value
    The CPU-specific page frame number where the section begins in
    memory.

 page_count

    OpenVMS usage:CPU-specific page count
    type:         longword (unsigned) on Alpha, quadword (unsigned)
                  on Integrity servers
    access:       read only
    mechanism:    by value
    Length of the page frame section in CPU-specific pages.

 acmode

    OpenVMS usage:access_mode
    type:         longword (unsigned)
    access:       read only
    mechanism:    by value
    Access mode that is to be the owner of the pages created during
    the mapping. The acmode argument is a longword containing the
    access mode.

    The $PSLDEF macro in STARLET.MLB and the file PSLDEF.H in
    SYS$STARLET_C.TLB define the following symbols and their values
    for the four access modes:

    Value      Symbolic Name      Access Mode

    0          PSL$C_KERNEL       Kernel
    1          PSL$C_EXEC         Executive
    2          PSL$C_SUPER        Supervisor
    3          PSL$C_USER         User

    The most privileged access mode used is the access mode of the
    caller. The calling process can delete pages only if those pages
    are owned by an access mode equal to or less privileged than the
    access mode of the calling process.

    Address space cannot be created within a region that has a create
    mode associated with it that is more privileged than the caller's
    mode. The condition value SS$_IVACMODE is returned if the caller
    is less privileged than the create mode for the region.

 flags

    OpenVMS usage:mask_longword
    type:         longword (unsigned)
    access:       read only
    mechanism:    by value
    Flag mask specifying the characteristics of the private section
    to be created. The flags argument is a longword bit vector in
    which each bit corresponds to a flag. The $SECDEF macro and the
    SECDEF.H file define a symbolic name for each flag. You construct
    the flags argument by performing a logical OR operation on the
    symbol names for all desired flags.

    The following table describes each flag that is valid for the
    $CRMPSC_PFN_64 service:

    Flag            Description

    SEC$M_ARGS64    Indicates that all parameters, specifically
                    start_pfn and page_count, are passed as 64-bit
                    numbers. This flag is ignored on OpenVMS Alpha
                    but must be set on Integrity server systems. If
                    the flag is not set on Integrity servers, the
                    error code SS$_IVSECFLG is returned.
    SEC$M_EXPREG    Pages are mapped into the first available space
                    at the current end of the specified region.
    SEC$M_NO_       Pages cannot overmap existing address space.
    OVERMAP         By default, pages can overmap existing address
                    space.
    SEC$M_PFNMAP    Pages form a page frame section. By default, this
                    flag is always present in this service and cannot
                    be disabled.
    SEC$M_          Flag that must be set when a PFN-mapped section
    UNCACHED        is created if this section must be treated
                    as uncached memory. Flag is ignored on Alpha
                    systems; it applies only to Integrity server
                    systems.
    SEC$M_WRT       Pages form a read/write section. By default,
                    pages form a read-only section.

    All other bits in the flags argument are reserved for future
    use by VSI and should be specified as 0. The condition value
    SS$_IVSECFLG is returned if any undefined bits are set or if
    an invalid combination of flags is set.

 return_va_64

    OpenVMS usage:address
    type:         quadword address
    access:       write only
    mechanism:    by 32- or 64-bit reference
    The lowest process virtual address into which the private page
    frame section was mapped. The return_va_64 argument is the 32- or
    64-bit virtual address of a naturally aligned quadword into which
    the service returns the virtual address.

 return_length_64

    OpenVMS usage:byte count
    type:         quadword (unsigned)
    access:       write only
    mechanism:    by 32- or 64-bit reference
    The length of the virtual address range mapped. The
    return_length_64 argument is the 32- or 64-bit virtual address
    of a naturally aligned quadword into which the service returns
    the length of the virtual address range in bytes.

 start_va_64

    OpenVMS usage:address
    type:         quadword address
    access:       read only
    mechanism:    by value
    The starting virtual address to map the private page frame
    section. The specified virtual address must be a CPU-specific
    page aligned address. If the flag SEC$M_EXPREG is specified, the
    start_va_64 argument must not be specified or must be specified
    as 0. If SEC$M_EXPREG is set and the start_va_64 argument is
    nonzero, the condition value SS$_IVESCFLG is returned.