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`MemAllocatePhysicallyContiguous`



 
LogicalAddress MemAllocatePhysicallyContiguous (

                     ByteCount byteSize,

                     Boolean clear);

--> byteSize: The number of bytes of memory to allocate.
--> clear: Whether or not the allocated memory is to be zeroed.

DESCRIPTION

MemAllocatePhysicallyContiguous allocates a buffer that is resident and is guaranteed to be physically uninterrupted. It returns the buffer's logical address.

Driver code can pass the address returned by MemAllocatePhysicallyContiguous to PrepareMemoryForIO to obtain the buffer's physical location.

EXECUTION CONTEXT

MemAllocatePhysicallyContiguous may be called only from task level, not from secondary or hardware interrupt level. Requesting a larger size especially anytime after your driver initially starts up is unlikely to succeed.

RESULT CODES

`noErr`	0	No error
`paramErr`	-50	Bad parameter
`memFullErr`	-108	Not enough room in heap