On 29/01/15 16:11, Terry Hoye wrote: > > Regarding GNU coreutils 8.12.197-032bb September 2011, > man md5sum states in part: > [quote] > The sums are computed as described in RFC 1321. When checking, the > input should be a former output of this program. The default mode is > to print a line with checksum, a character indicating type (`*' for > binary, ` ' for text), and name for each FILE.[/quote] > > I think I am correct in the following observation: > Taken literally, the second sentence is incorrect. The default mode has > two characters, often both spaces, between the two stringsets.
True. The attached should make this more accurate. > I don't think the algorithm works correctly with only one space between the > stringsets. Well --check still works in this case as it's switching to "bsd reversed" mode. I.E. supporting the output from `md5 -r` etc. I've made this clearer also, in the info docs. thanks, Pádraig.
From ecc8f8104893f1eaae8a8e7e3e55c8c42f4c7206 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?P=C3=A1draig=20Brady?= <[email protected]> Date: Thu, 29 Jan 2015 18:44:41 +0000 Subject: [PATCH] doc: clarify the output format for the *sum utilities * src/md5sum.c (usage): Detail the reasons for the default double space between checksum and file name. * doc/coreutils.texi (md5sum invocation): Likewise. Explicitly mention the 3 formats that --check supports. Fixes http://bugs.gnu.org/19725 --- doc/coreutils.texi | 15 ++++++++++----- src/md5sum.c | 6 +++--- 2 files changed, 13 insertions(+), 8 deletions(-) diff --git a/doc/coreutils.texi b/doc/coreutils.texi index 99c7df3..0a82b65 100644 --- a/doc/coreutils.texi +++ b/doc/coreutils.texi @@ -4057,8 +4057,11 @@ consistent. Synopsis: md5sum [@var{option}]@dots{} [@var{file}]@dots{} @end example -For each @var{file}, @samp{md5sum} outputs the MD5 checksum, a flag -indicating binary or text input mode, and the file name. +For each @var{file}, @samp{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 @samp{*}, text mode with @samp{ } (space). +Binary mode is the default on systems where it's significant, +otherwise text mode is the default. If @var{file} contains a backslash or newline, the line is started with a backslash, and each problematic character in the file name is escaped with a backslash, making the output @@ -4089,9 +4092,11 @@ Read file names and checksum information (not data) from each whether the checksums match the contents of the named files. The input to this mode of @command{md5sum} is usually the output of a prior, checksum-generating run of @samp{md5sum}. -Each valid line of input consists of an MD5 checksum, a binary/text -flag, and then a file name. -Binary mode is indicated with @samp{*}, text with @samp{ } (space). +Three input formats are supported. Either the default output +format described above, the @option{--tag} output format, +or the BSD reversed mode format which is similar to the default mode, +but doesn't use a character to distinguish binary and text modes. +@sp 1 For each such line, @command{md5sum} reads the named file and computes its MD5 checksum. Then, if the computed message digest does not match the one on the line with the file name, the file is noted as having diff --git a/src/md5sum.c b/src/md5sum.c index a60e2ff..8c5f876 100644 --- a/src/md5sum.c +++ b/src/md5sum.c @@ -206,9 +206,9 @@ The following four options are useful only when verifying checksums:\n\ printf (_("\ \n\ The sums are computed as described in %s. When checking, the input\n\ -should be a former output of this program. The default mode is to print\n\ -a line with checksum, a character indicating input mode ('*' for binary,\n\ -space for text), and name for each FILE.\n"), +should be a former output of this program. The default mode is to print a\n\ +line with checksum, a space, a character indicating input mode ('*' for binary,\ +\n' ' for text or where binary is insignificant), and name for each FILE.\n"), DIGEST_REFERENCE); emit_ancillary_info (PROGRAM_NAME); } -- 2.1.0
