linux - Can mmap and O_DIRECT be used together? -

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as understand it, when mmap file mapping pages page cache file directly process, , when use o_direct bypassing page cache. ever make sense use 2 together? if understanding right how work? mmap seems rely on file being in page cache , o_direct seems prevent going there (assuming nothing else on system has file open). found this question answerer seems think it's normal do.


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