Usage: shred [OPTIONS] FILE [...]
Overwrite the specified FILE(s) repeatedly, in order to make it harder
for even very expensive hardware probing to recover the data.
-f, --force change permissions to allow writing if necessary
-n, --iterations=N Overwrite N times instead of the default (25)
-s, --size=N shred this many bytes (suffixes like k, M, G accepted)
-u, --remove truncate and remove file after overwriting
-v, --verbose show progress
-x, --exact do not round file sizes up to the next full block
-z, --zero add a final overwrite with zeros to hide shredding
- shred standard output
--help display this help and exit
--version print 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. When operating on regular
files, most people use the --remove option.
CAUTION: Note that shred relies on a very important assumption:
that the filesystem overwrites data in place. This is the traditional
way to do things, but many modern filesystem designs do not satisfy this
assumption. The following are examples of filesystems on which shred is
not effective:
* log-structured or journaled filesystems, such as those supplied with
AIX and Solaris (and JFS, ReiserFS, XFS, etc.)
* filesystems that write redundant data and carry on even if some writes
fail, such as RAID-based filesystems
* filesystems that make snapshots, such as Network Appliance's NFS server
* filesystems that cache in temporary locations, such as NFS
version 3 clients
* compressed filesystems
Report bugs to <
[email protected]>.