HELPLIB.HLB  —  System Services, $CRETVA
    Adds a range of demand-zero allocation pagelets to a process's
    virtual address space for the execution of the current image.

    Format

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

    C Prototype

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

                      *retadr, unsigned int acmode);

1  –  Arguments

 inadr

    OpenVMS usage:address_range
    type:         longword (unsigned)
    access:       read only
    mechanism:    by reference
    Address of a 2-longword array containing the starting and ending
    virtual addresses of the pages to be created. If the starting and
    ending virtual addresses are the same, a single page is created.
    The addresses are adjusted up or down to fall on CPU-specific
    page boundaries. Only the virtual page number portion of the
    virtual address is used; the low order byte-within-page bits are
    ignored.

 retadr

    OpenVMS usage:address_range
    type:         longword (unsigned)
    access:       write only
    mechanism:    by reference-array reference or descriptor
    Address of a 2-longword array to receive the starting and ending
    virtual addresses of the pages created.

    On Alpha and Integrity server systems, the retadr argument should
    be checked by programs for actual allocation. Because the Alpha
    and Integrity servers architectures define more than one page
    size, more space might be created than was specified in the inadr
    argument.

 acmode

    OpenVMS usage:access_mode
    type:         longword (unsigned)
    access:       read only
    mechanism:    by value
    Access mode and protection for the new pages. The acmode argument
    is a longword containing the access mode.

    The $PSLDEF macro defines the following symbols for the four
    access modes:

    Symbol         Access Mode

    PSL$C_KERNEL   Kernel
    PSL$C_EXEC     Executive
    PSL$C_SUPER    Supervisor
    PSL$C_USER     User

    The most privileged access mode used is the access mode of
    the caller. The protection of the pages is read/write for the
    resultant access mode and those more privileged.
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