NAME

       shred  -  Overwrite  the specified FILE(s) repeatedly, in order to make it harder for even very expensive
       hardware probing to recover the data.

SYNOPSIS

       shred [-f|--force] [-n|--iterations] [-s|--size] [-u ] [--remove] [-v|--verbose] [-x|--exact] [-z|--zero]
       [-h|--help] [-V|--version] [file]

DESCRIPTION

       Overwrite the specified FILE(s) repeatedly, in order to make it harder for even very  expensive  hardware
       probing to recover the data.

OPTIONS

       -f, --force
              change permissions to allow writing if necessary

       -n, --iterations=NUMBER [default: 3]
              overwrite N times instead of the default (3)

       -s, --size=N
              shred this many bytes (suffixes like K, M, G accepted)

       -u     deallocate and remove file after overwriting

       --remove=HOW
              like -u but give control on HOW to delete;  See below

              [possible values: unlink, wipe, wipesync]

       -v, --verbose
              show progress

       -x, --exact
              do not round file sizes up to the next full block; this is the default for non-regular files

       -z, --zero
              add a final overwrite with zeros to hide shredding

       -h, --help
              Print help

       -V, --version
              Print version

       [file]

EXTRA

       Delete  FILE(s)  if  --remove  (-u)  is  specified.  The default is not to remove the files because it is
       common to operate on device files like /dev/hda, and those files usually should not be removed.

       CAUTION: Note that shred relies on a very important assumption: that the file system overwrites  data  in
       place.  This is the traditional way to do things, but many modern file system designs do not satisfy this
       assumption.   The  following  are  examples  of  file  systems on which shred is not effective, or is not
       guaranteed to be effective in all file system modes:

        * log-structured or journal file systems, such as those supplied with
          AIX and Solaris (and JFS, ReiserFS, XFS, Ext3, etc.)

        * file systems that write redundant data and carry on even if some writes
          fail, such as RAID-based file systems

        * file systems that make snapshots, such as Network Appliance's NFS server

        * file systems that cache in temporary locations, such as NFS
          version 3 clients

        * compressed file systems

       In the case of  ext3  file  systems,  the  above  disclaimer  applies  (and  shred  is  thus  of  limited
       effectiveness) only in data=journal mode, which journals file data in addition to just metadata.  In both
       the  data=ordered  (default)  and  data=writeback  modes, shred works as usual. Ext3 journal modes can be
       changed by adding the data=something option to the mount options for a  particular  file  system  in  the
       /etc/fstab file, as documented in the mount man page (man mount).

       In  addition,  file  system  backups  and  remote  mirrors  may contain copies of the file that cannot be
       removed, and that will allow a shredded file to be recovered later.

VERSION

       v0.0.24

                                                  shred 0.0.24                                          shred(1)