VMS Help System Services, $MGBLSC GPFN 64 (Alpha Only), Arguments  *Conan The Librarian (sorry for the slow response - running on an old VAX)

 gs_name_64

    OpenVMS usage:section_name
    type:         character-coded text string
    access:       read only
    mechanism:    by 32- or 64-bit descriptor-fixed-length string
                  descriptor
    Name of the global section. The gs_name argument is the 32- or
    64-bit virtual address of a naturally aligned 32-bit or 64-bit
    descriptor pointing to this name string.

    You can specify any name from 1 to 43 characters. All processes
    mapping to the same global section must specify the same name.
    Note that the name is case sensitive.

    Use of characters valid in logical names is strongly encouraged.
    Valid values include alphanumeric characters, the dollar sign
    ($), and the underscore (_). If the name string begins with an
    underscore (_), the underscore is stripped and the resultant
    string is considered to be the actual name. Use of the colon (:)
    is not permitted.

    Names are first subject to a logical name translation, after
    the application of the prefix GBL$ to the name. If the result
    translates, it is used as the name of the section. If the
    resulting name does not translate, the name specified by the
    caller is used as the name of the section.

    Additional information on logical name translations and on
    section name processing is available in the OpenVMS Programming
    Concepts Manual.

 ident_64

    OpenVMS usage:section_id
    type:         quadword (unsigned)
    access:       read only
    mechanism:    by 32- or 64-bit reference
    Identification value specifying the version number of a global
    section. The ident_64 argument is a quadword containing three
    fields. The ident_64 argument is the 32- or 64-bit virtual
    address of a naturally aligned quadword that contains the
    identification value.

    The first longword specifies the matching criteria in its low-
    order two bits. The valid values, symbolic names by which they
    can be specified, and their meanings are as follows:

           Symbolic
    Value  Name           Match Criteria

    0      SEC$K_MATALL   Match all versions of the section.
    1      SEC$K_MATEQU   Match only if major and minor
                          identifications match.
    2      SEC$K_MATLEQ   Match if the major identifications are
                          equal and the minor identification of the
                          mapper is less than or equal to the minor
                          identification of the global section.

    If you specify the ident_64 argument as 0, the version number and
    match control fields default to 0.

    The version number is in the second longword. The version number
    contains two fields: a minor identification in the low-order 24
    bits and a major identification in the high-order 8 bits. You
    can assign values for these fields by installation convention to
    differentiate versions of global sections. If no version number
    is specified when a section is created, processes that specify a
    version number when mapping cannot access the global section.

 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.

 relative_page

    OpenVMS usage:CPU-specific page count
    type:         longword (unsigned)
    access:       read only
    mechanism:    by value
    Relative CPU-specific page number within the global section to
    start mapping.

 page_count

    OpenVMS usage:CPU-specific page count
    type:         longword (unsigned)
    access:       read only
    mechanism:    by value
    Length of mapping in CPU-specific pages. If zero is specified,
    the global page frame section is mapped to the end of the
    section.

 acmode

    OpenVMS usage:access-mode
    type:         longword (unsigned)
    access:       read only
    mechanism:    by value
    Access mode to be associated with the pages mapped into the
    process virtual address space. The acmode argument is a longword
    containing the access mode. The $PSLDEF macro defines symbols for
    the four access modes.

    The most privileged access mode used is the access mode of the
    caller. 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 options for the operation. 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
    $MGBLSC_GPFN_64 service:

    Flag          Description

    SEC$M_GBL     Pages form a global section. By default, this flag
                  is always present in this service and cannot be
                  disabled.

    SEC$M_EXPREG  Map the section into the first available space at
                  the current end of the specified region. If this
                  flag is specified, the start_va_64 argument is not
                  used.

    SEC$M_PERM    Pages are permanent. By default, this flag is
                  always present in this service and cannot be
                  disabled.

    SEC$M_PFNMAP  Pages form a page frame section. By default, this
                  flag is always present in this service and cannot
                  be disabled.

    SEC$M_PAGFIL  Pages form a global page-file section. SEC$M_PAGFIL
                  also implies SEC$M_WRT and SEC$M_DZRO.

    SEC$M_SYSGBL  Map a system global section. By default, the
                  section is a group global section.

    SEC$M_WRT     Map the section with read/write access. By default,
                  the section is mapped with read-only access. If
                  SEC$M_WRT is specified, write access is required.

    All other bits in the flags argument are reserved for future
    use by Compaq and should be specified as 0. The condition value
    SS$_IVSECFLG is returned if any undefined bits are set or if an
    illegal 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 global page
    frame section was mapped. The return_va_64 argument is the 32-
    or 64-bit virtual address of a naturally aligned quadword that
    contains the virtual address.

 return_length_64

    OpenVMS usage:byte count
    type:         quadword (unsigned)
    access:       write only
    mechanism:    by 32- or 64-bit reference
    The 32- or 64-bit virtual address of a naturally aligned quadword
    into which the $MGBLSC_GPFN_64 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 global section. The
    specified virtual address must be a CPU-specified 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$_IVSECFLG is returned.

    Always refer to the return_va_64 and return_length_64 arguments
    to determine the range of virtual addresses mapped.