Linux in a Nutshell, 6th Edition

Name

shred

Synopsis

shred [options] files

Overwrite a file to make the contents unrecoverable, and delete the file afterward if requested.

Options

-

Shred standard output.

-f, --force

Force permissions to allow writing to files.

--help

Print help message and exit.

-nnum, --iterations=num

Overwrite files num times (default is 25).

--random-source=file

Use file as the source of random bytes for overwriting. Default is /dev/urandom.

-snum, --size=num

Shred num bytes. num can be expressed with suffixes (e.g., K, M, or G).

-u, --remove

Remove file after overwriting. shred does not remove the file unless this option is specified.

-v, --verbose

Verbose mode.

--version

Print version information and exit.

-x, --exact

Shred the exact file size; do not round up to the next full block.

-z, --zero

On the final pass, overwrite with zeros to hide the shredding.