Allocation Flags

Header: Files.h

Indicate how new space is to be allocated.

enum {
    kFSAllocDefaultFlags = ,
    kFSAllocAllOrNothingMask = 1,
    kFSAllocContiguousMask = 2,
    kFSAllocNoRoundUpMask = 4,
    kFSAllocReservedMask = 65528
};

Constant descriptions

kFSAllocDefaultFlags: Allocate as much as possible, not necessarily contiguous.
kFSAllocAllOrNothingMask: This bit is set when an allocation must allocate the total requested amount, or else fail with nothing allocated; when this bit is not set, the allocation may complete successfully but allocate less than requested.
kFSAllocContiguousMask: This bit is set when an allocation should allocate one contiguous range of space on the volume. If this bit is clear, multiple discontiguous extents may be allocated to fulfill the request.
kFSAllocNoRoundUpMask: This bit is set when an allocation should no round up to the clump size. If ths bit is clear, then additional space beyond the amount requested may be allocated; this is done by some volume formats (including HFS and HFS Plus) to avoid many small allocation requests. If the bit is set, no additional allocation is done (except where required by the volume format, such as rounding up to a multiple of the allocation block size).
kFSAllocReservedMask: Reserved; set to zero.