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FALLOCATE(1)							  FALLOCATE(1)

NAME
       fallocate - preallocate space to a file.

SYNOPSIS
       fallocate [-n] [-p] [-o offset] -l length filename

DESCRIPTION
       fallocate  is  used  to	preallocate blocks to a file.  For filesystems
       which support the fallocate system call, this is done quickly by	 allo‐
       cating blocks and marking them as uninitialized, requiring no IO to the
       data blocks.  This is much faster than creating a file  by  filling  it
       with zeros.

       As  of the Linux Kernel v2.6.31, the fallocate system call is supported
       by the btrfs, ext4, ocfs2, and xfs filesystems.

       The exit code returned by fallocate is 0 on success and 1 on failure.

OPTIONS
       -h, --help
	      Print help and exit.

       -n, --keep-size
	      Do not modify the apparent length of the file. This  may	effec‐
	      tively  allocate	blocks	past  EOF, which can be removed with a
	      truncate.

       -p, --punch-hole
	      Punch holes in the file, the range should not exceed the	length
	      of the file.

       -o, --offset offset
	      Specifies	 the  beginning	 offset	 of  the allocation, in bytes.
	      Suffixes of k, m, g, t, p, e may be  specified  to  denote  KiB,
	      MiB, GiB, etc.

       -l, --length length
	      Specifies	 the  length of the allocation, in bytes.  Suffixes of
	      k, m, g, t, p, e may be specified to denote KiB, MiB, GiB, etc.

AUTHORS
       Eric Sandeen <sandeen@redhat.com>
       Karel Zak <kzak@redhat.com>

SEE ALSO
       fallocate(2), posix_fallocate(3), truncate(1)

AVAILABILITY
       The fallocate command is part  of  the  util-linux-ng  package  and  is
       available from ftp://ftp.kernel.org/pub/linux/utils/util-linux-ng/.

Version 1.0			   Jul 2009			  FALLOCATE(1)

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