Subject: Re: bug#14108: Bug in dd

From: Bob Proulx <[email-masked]>
Date: Sun, 31 Mar 2013 22:58:15 -0600

tag 14108 + notabug
close 14108
thanks

Haneef Mubarak wrote:
> dd doesn't have a quiet option, ie: dd --quiet
> 
> Having a quiet option would allow for an easier use of piping with dd

The dd manual documents this as "status=none":

  `status=WHICH'
     Transfer information is normally output to stderr upon receipt of
     the `INFO' signal or when `dd' exits.  Specifying WHICH will
     identify which information to suppress.

    `noxfer'
          Do not print the transfer rate and volume statistics that
          normally make up the last status line.

    `none'
          Do not print any informational messages to stderr.  Error
          messages are output as normal.

Example of use of it.

  $ dd if=/dev/zero of=/dev/null bs=1k count=1
  1+0 records in
  1+0 records out
  1024 bytes (1.0 kB) copied, 0.000113146 s, 9.1 MB/s

  $ dd status=none if=/dev/zero of=/dev/null bs=1k count=1
  ...no output...

The dd command is an old command and the option syntax doesn't follow
the same as what we would say is the normal modern style.  It follows
the previous style.  Therefore it won't be --quiet there.  It will be
something=something.  Traditionally dd does not support the
status=none usage.  GNU dd has extended this with the status=none
option to supress the normal stats output.  However errors are
reported normally.

  $ dd if=/dev/zero of=/dev/full bs=1k count=1
  dd: writing ‘/dev/full’: No space left on device
  1+0 records in
  0+0 records out
  0 bytes (0 B) copied, 0.000184665 s, 0.0 kB/s

Bob