Re: sha256sum --text generating blank spaces and hyphens?

["Thomas Schmitt" <scdbackup@gmx.net>]

Hi,

Albretch Mueller wrote:
> > >  I am trying to avoid funky characters and sha256sum --text still
> > > generates them!?!

Andy Smith wrote:
> > If you're referring to the space and then the file name ("-" in case
> > of stdin) on the end, you can just select only the first output up
> > to whitespace with e.g. awk:

> Yes, you could but I am trying to find out why this is happening
> instead of truncating the string when a space appears because I don't
> think what would be safe.

One of the blanks and the hyphen-or-minus are announced by the man page:

  The default mode is
  to print a line with checksum, a character indicating input  mode  ('*'
  for binary, space for text), and name for each FILE.

"FILE" is the minus-sign for standard input. The second blank is there
to indicate the text mode of sha256sum.
Only the first blank is somewhat puzzling. But it's always there.

  https://www.gnu.org/software/coreutils/manual/html_node/sha2-utilities#sha2-utilities
points to
  https://www.gnu.org/software/coreutils/manual/html_node/md5sum-invocation.html
which says
  For each file, ‘md5sum’ outputs by default, the MD5 checksum, a space,
  a flag indicating binary or text input mode, and the file name. Binary
  mode is indicated with ‘*’, text mode with ‘ ’ (space). Binary mode is
  the default on systems where it’s significant, otherwise text mode is
  the default. The cksum command always uses binary mode and a ‘ ’
  (space) flag.

So the first blank can be relied on and thus the proposal by Andy Smith
to use "awk '{print $1}'" is valid.


Have a nice day :)

Thomas