ioctl12.hlp (Topic list)
SCR_ALLOCLDT (1.2)
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#define INCL_DOSDEVIOCTL
 
USHORT DosDevIOCtl(psel, pvAddrInfo, 0x0070, 0x0003, hDevice)
PSEL psel;           /* pointer to LDT selector                */
PVOID pvAddrInfo;    /* pointer to structure with address info */
HFILE hDevice;       /* device handle                          */
 
The SCR_ALLOCLDT function allocates a logical descriptor table (LDT)
selector for an area of memory.
 
Parameter   Description
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psel        Points to the logical descriptor table selector for the memory
            area specified by the LDTADDRINFO structure.
 
pvAddrInfo  Points to the LDTADDRINFO structure that contains the address
            and size of memory for which a selector is requested.
 
hDevice     Identifies the screen device that receives the device-control
            function. This handle must have been created previously by using
            the DosOpen function.
 
Return Value
 
The return value is zero if the function is successful or the error value
ERROR_I24_INVALID_PARAMETER if an error occurs.
 
Comments
 
Read/Write access is granted to data areas completely contained in the
address range 0xA0000 through 0xBFFFF. Read-only access is granted to data
areas outside this range, but inside the range 0x00000 through 0xFFFFF.
Attempts to access any address outside this range results in an error.
 
See Also
 
SCR_ALLOCLDTOFF, SCR_DEALLOCLDT, LDTADDRINFO