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    SubjectRe: [PATCH 1/2] fs: add SEEK_HOLE and SEEK_DATA flags
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    On Thu, 21 Apr 2011 15:42:33 EDT, Josef Bacik said:

    > -SEEK_HOLE: this moves the file pos to the nearest hole in the file from the
    > given position.

    Do we want the semantic to be "the nearest" hole? Or did we really want "the
    next" hole? Loops like a bullet loaded in the chamber and pointed at the
    programmer's foot if they aren't allowing for the fact that this can go
    *backwards* in the file if the closest hole is towards the beginning. Good way
    to end up in an infinite loop or other messy...

    Consider the obvious implementation of "skip over a hole" - lseek(SEEK_HOLE),
    lseek(SEEK_DATA). and start reading data because we've skipped over the hole.
    Wrong - the second seek may have gone backwards if the data was only 4K away
    but the hole was 64K in size...

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