NTFSFALLOCATE(8)           (June 2014)           NTFSFALLOCATE(8)

          ntfsfallocate - preallocate space to a file on an NTFS

          ntfsfallocate [options] -l length device file [attr-type

          ntfsfallocate preallocates space for any attribute of a file
          or directory, thus reserving space before actual contents is
          written. This is similar to fallocate(1).

          Below is a summary of all the options that ntfsfallocate
          accepts.  Nearly all options have two equivalent names.  The
          short name is preceded by - and the long name is preceded by
          --.  Any single letter options, that don't take an argument,
          can be combined into a single command, e.g.  -fv is equiva-
          lent to -f -v.  Long named options can be abbreviated to any
          unique prefix of their name.

          -f, --force
               This will override some sensible defaults, such as not
               using a mounted volume.  Use this option with caution.

          -h, --help
               Show a list of options with a brief description of each

          -l, --length LENGTH
               This is a mandatory option to specify the number of
               bytes to preallocate.  It will be rounded up to a mul-
               tiple of the cluster size.  A suffix of K, M, G, T, P
               or E may be appended to mean a multiplicative factor of
               a power of 1000. Similarly a suffix of Ki, Mi, Gi, Ti,
               Pi or Ei may be appended to mean a multiplicative fac-
               tor of a power of 1024.

          -n, --no-size-change
               Do not change the apparent size of the file. The space
               allocated beyond the apparent size is not zeroed, but
               subsequent writing beyond the apparent end of file will
               force zeroing the inner allocated space as it cannot be
               considered as a hole any more, and this may take sig-
               nificant time.

          -N, --no-action
               Simulate the allocation without actually write to

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          -o, --offset OFFSET
               Specify the offset in the file where preallocation
               starts. By default, the preallocation is counted from
               the beginning of the file. Space already allocated in
               the area defined by offset and length is preserved.

          -q, --quiet
               Suppress some debug/warning/error messages.

          -v, --verbose
               Display more debug/warning/error messages.

          -V, --version
               Show the version number, copyright and license of

               Define a particular attribute type to be preallocated
               (advanced use only).  By default, the unnamed $DATA
               attribute (the contents of a plain file) will be preal-
               located. The attribute has to be specified by a number
               in decimal or hexadecimal : box; lB lB lB l l l.
               Hex  Decimal   Name 0x10 16   "$STANDARD_INFORMATION"
               0x20 32   "$ATTRIBUTE_LIST" 0x30 48   "$FILE_NAME"
               0x40 64   "$OBJECT_ID" 0x50 80   "$SECURITY_DESCRIPTOR"
               0x60 96   "$VOLUME_NAME"
               0x70 112  "$VOLUME_INFORMATION" 0x80 128  "$DATA"
               0x90 144  "$INDEX_ROOT" 0xA0 160  "$INDEX_ALLOCATION"
               0xB0 176  "$BITMAP" 0xC0 192  "$REPARSE_POINT"
               0xD0 208  "$EA_INFORMATION" 0xE0 224  "$EA"
               0xF0 240  "$PROPERTY_SET"
               0x100     256  "$LOGGED_UTILITY_STREAM"

               Define the name of the particular attribute type to be
               preallocated (advanced use only).

          Preallocate 100MB to the file database.db located in the
          Data directory which is at the root of an NTFS file system.

               ntfsfallocate -l 100M /dev/sda1 Data/database.db

          There are no known problems with ntfsfallocate, however it
          can lead to configurations not supported by Windows and Win-
          dows may crash (BSOD) when writing to preallocated clusters
          which were not written to earlier. Files with preallocated
          space should be fully be written to before they are updated
          by Windows.

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          If you find a bug in ntfsfallocate proper, please send an
          email describing the problem to the development team:

          ntfsfallocate was written by Jean-Pierre Andre.

          ntfsfallocate is part of the ntfs-3g package and is avail-
          able from:

          ntfs-3g(8), ntfstruncate(8), ntfsprogs(8), fallocate(1)

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