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SetFile.AdvanceOnly

OSR_Community_UserOSR_Community_User Member Posts: 110,217
Can anyone tell me exactly where when and how the 'AvanceOnly' flag
of the SetFile parameter is used?
Thanks

Comments

  • OSR_Community_UserOSR_Community_User Member Posts: 110,217
    Advance only is set when the Cache Manager is trying to ensure the file is
    of sufficient size. In general, the VM system does not do paging I/O writes
    that extend the size of the file.

    Regards,

    Tony Mason
    Consulting Partner
    OSR Open Systems Resources, Inc.
    http://www.osr.com <http://www.osr.com&gt;


    -----Original Message-----
    From: Smith, Joel [mailto:[email protected]]
    Sent: Monday, May 08, 2000 2:51 PM
    To: File Systems Developers
    Subject: [ntfsd] SetFile.AdvanceOnly




    Can anyone tell me exactly where when and how the 'AvanceOnly' flag
    of the SetFile parameter is used?
    Thanks
  • OSR_Community_UserOSR_Community_User Member Posts: 110,217
    Specifically, AdvanceOnly is used by the cache manager to tell the FSD to
    update the file's ValidDataLength, not to allocate storage. The storage was
    already allocated by a previous IRP_MJ_SET_INFORMATION. Accordingly, NTFS
    uses the AdvanceOnly flag to increase the ValidDataLength, and does not
    allocate additional storage. Since FASTFAT has no concept of
    ValidDataLength, it uses the AdvanceOnly flag to update the file size stored
    in the directory entry, but does not allocate storage.

    > -----Original Message-----
    > From: Tony Mason [mailto:[email protected]]
    > Sent: Monday, May 08, 2000 1:52 PM
    > To: File Systems Developers
    > Subject: [ntfsd] RE: SetFile.AdvanceOnly
    >
    >
    > Advance only is set when the Cache Manager is trying to
    > ensure the file is
    > of sufficient size. In general, the VM system does not do
    > paging I/O writes
    > that extend the size of the file.
    >
    > Regards,
    >
    > Tony Mason
    > Consulting Partner
    > OSR Open Systems Resources, Inc.
    > http://www.osr.com <http://www.osr.com&gt;
    >
    >
    > -----Original Message-----
    > From: Smith, Joel [mailto:[email protected]]
    > Sent: Monday, May 08, 2000 2:51 PM
    > To: File Systems Developers
    > Subject: [ntfsd] SetFile.AdvanceOnly
    >
    >
    >
    >
    > Can anyone tell me exactly where when and how the
    > 'AvanceOnly' flag
    > of the SetFile parameter is used?
    > Thanks
    >
    >
    > ---
    > You are currently subscribed to ntfsd as: [email protected]
    > To unsubscribe send a blank email to $subst('Email.Unsub')
    >
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