I'd rather we just get the oft-discussed punch() syscall instead.
This is really what "unallocate" would do for persistent allocations
and it would be useful for files that were not preallocated.
For filesystems that don't implement punch glibc() would do zero-filling
of the punched area I guess (to make it equivalent to reading from a
hole in the file).
Cheers, Andreas
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Andreas Dilger
Principal Software Engineer
Cluster File Systems, Inc.
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