GNU bug report logs - #19604
echo --help does not work

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Message #21 received at 19604 <at> debbugs.gnu.org (full text, mbox):

From: Bernhard Voelker <mail <at> bernhard-voelker.de>
To: prateek goyal <prateek.goyal5 <at> gmail.com>, Eric Blake <eblake <at> redhat.com>
Cc: 19604 <at> debbugs.gnu.org, Pádraig Brady <P <at> draigbrady.com>
Subject: Re: bug#19604: echo --help does not work
Date: Fri, 16 Jan 2015 10:49:06 +0100

On 01/15/2015 04:55 PM, prateek goyal wrote:
> So even if I execute following command, it gives same result:

> prateek <at> prateek-pc:~/Documents/awk$ env POSIXLY_CORRECT=1 echo --help
> --help

That is exactly what Eric said before: POSIX mandates to literally
output the string "--help" - which coreutils' echo does if the variable
POSIXLY_CORRECT is set.  Otherwise, the implementation extends the
functionality and adheres to GNU standards which mandates to honor
the "--help" option to output the usage message:

  $ env --unset=POSIXLY_CORRECT echo --help
  Usage: ...

Maybe you were confused by the use of the 'env' utility.
You'll get the same by specifying the echo with it's absolute path:

  $ which echo
  /usr/bin/echo
  $ unset POSIXLY_CORRECT
  $ /usr/bin/echo --help
  Usage: [...]

Have a nice day,
Berny

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