flag (ULONG) - input

      Allocation attribute and desired access protection flags.

      A set of flags describing the allocation attributes and desired access protection for the shared memory object. Possible values are shown in the following lists:

      Allocation Attributes

      PAG_COMMIT (0x00000010)

        All pages in the shared memory object are initially committed.
      OBJ_GIVEABLE (0x00000200)
        The access to the memory object can be given to another process using the DosGiveSharedMem function.
      OBJ_GETTABLE (0x00000100)
        The memory object can be accessed by another process that knows the address of the memory and calls the DosGetSharedMem function.
      OBJ_TILE (0x00000040)
        The shared memory object must be allocated in the first 512MB of virtual-address space, with 16-bit selectors mapping the memory object.

        The 16-bit selectors are allocated to map the 32-bit object at 64KB boundaries. The figure in the description of the Parameters for DosAllocMem shows how the 16-bit alias selectors map the 32-bit object. Desired Access Protection

      PAG_EXECUTE (0x00000004)
        Execute access to the committed pages in the private memory object is desired.
      PAG_READ (0x00000001)
        Read access is desired.
      PAG_WRITE (0x00000002)
        Write access is desired.
      PAG_GUARD (0x00000008),
        Access to the committed pages in the private memory object causes a "guard page entered" condition to be raised in the subject process.
      At least one of the bits of PAG_READ, PAG_WRITE, or PAG_EXECUTE must be set.


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