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in reply to Re-Creating a file does not change inode modification time (Windows)

Some filesystems do not modify the “modification time” because it is expensive to do so.   Especially on some network filesystems, this creates a large number of disk writes to the directory blocks with no pragmatic purpose or benefit.   Therefore, these timestamps should not be regarded as a reliable indicator of modification, regardless of the operating-system.

  • Comment on Re: Re-Creating a file does not change inode modification time (Windows)

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Re^2: Re-Creating a file does not change inode modification time (Windows)
by wwe (Friar) on Sep 16, 2011 at 07:59 UTC
    Fully ack. You may switch off modification time update even on local NTFS file system which is enabled by default. Check if the modification date changes by running stat file multiple times if you update the file outside from perl. If yes the problem is related to the script.
Re^2: Re-Creating a file does not change inode modification time (Windows)
by armstd (Friar) on Sep 17, 2011 at 14:08 UTC

    Usually it's access time/atime that gets disabled, not mtime. Access might be read-only, so updating atime introduces write i/o to the FS. Modifications are by definition write i/o, so it's cost effective to update mtime also.

    --Dave

Re^2: Re-Creating a file does not change inode modification time (Windows)
by rovf (Priest) on Sep 20, 2011 at 08:19 UTC
    Just to make it clear: I'm not talking about file modification time (mtime), but about inode modification time (ctime). Sorry if I was not precise enough about this.

    -- 
    Ronald Fischer <ynnor@mm.st>