NAME
shred —
zero and unlink files
SYNOPSIS
shred |
[-fvzx] [-s
size] [-n
iterations]
[-u|--remove[=how]]
[--random-source=path]
file… |
DESCRIPTION
Writes NUL bytes until end of files
(standard output stream if "-"), then removes
them if -u is specified.
Don't use this.
If you think you need this: don't. Secure-TRIM flash media,
single-pass dd
if=/dev/zero over magnetic
media. Or just burn it. You may be tempted to use this on regular files:
don't. Just remove them instead of making more copies by overwriting them
again.
OPTIONS
-f,--force- Change mode to
0200(write for owner) if opening file failed withEACCESS. -u,--remove[=how]- Remove file after writing to it.
-v,--verbose- Log status to the standard error stream.
-s,--size=size- Write size NULs instead of the file length. Same format as stdbuf(1).
-z,--zero- All below ignored.
--random-source=path-n,--iterations=count-x,--exact
HISTORY
Originates from the GNU system, where it purports to
Overwrite the specified FILE(s) repeatedly, in order
to make it harder for even very expensive hardware probing to recover the
data.
This is laughable, of course.