shred(1) — Linux manual page


SHRED(1)                      User Commands                     SHRED(1)

NAME         top

       shred - overwrite a file to hide its contents, and optionally
       delete it

SYNOPSIS         top

       shred [OPTION]... FILE...

DESCRIPTION         top

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

       If FILE is -, shred standard output.

       Mandatory arguments to long options are mandatory for short
       options too.

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

       -n, --iterations=N
              overwrite N times instead of the default (3)

              get random bytes from FILE

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

       -u     deallocate and remove file after overwriting

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

       -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

       --help display this help and exit

              output version information and exit

       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.  The optional HOW parameter indicates how to remove a
       directory entry: 'unlink' => use a standard unlink call.  'wipe'
       => also first obfuscate bytes in the name.  'wipesync' => also
       sync each obfuscated byte to the device.  The default mode is
       'wipesync', but note it can be expensive.

       CAUTION: shred assumes the file system and hardware overwrite
       data in place.  Although this is common, many platforms operate
       otherwise.  Also, backups and mirrors may contain unremovable
       copies that will let a shredded file be recovered later.  See the
       GNU coreutils manual for details.

AUTHOR         top

       Written by Colin Plumb.

REPORTING BUGS         top

       GNU coreutils online help:
       Report any translation bugs to

COPYRIGHT         top

       Copyright © 2023 Free Software Foundation, Inc.  License GPLv3+:
       GNU GPL version 3 or later <>.
       This is free software: you are free to change and redistribute
       it.  There is NO WARRANTY, to the extent permitted by law.

SEE ALSO         top

       Full documentation <>
       or available locally via: info '(coreutils) shred invocation'

COLOPHON         top

       This page is part of the coreutils (basic file, shell and text
       manipulation utilities) project.  Information about the project
       can be found at ⟨⟩.  If you
       have a bug report for this manual page, see
       ⟨⟩.  This page was obtained
       from the tarball coreutils-9.4.tar.xz fetched from
       ⟨⟩ on 2023-12-22.  If you
       discover any rendering problems in this HTML version of the page,
       or you believe there is a better or more up-to-date source for
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       manual page), send a mail to

GNU coreutils 9.4              August 2023                      SHRED(1)

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