Re: etags name collision.

["Alfred M. Szmidt" <ams@gnu.org>]

   >   >Not all systems use Exuberant Ctags or Universal Ctags.  On the BSDs,
   >   >ctags is compatible with the Emacs ctags output (which is why it
   >   >exists, AFAIR).  Exuberant Ctags etc do not work with either vi(1) or
   >   >mg(1) on those systems, and their output is at odds with what is
   >   >standardized by POSIX.
   >
   >   In what sense it is not standarized by POSIX?
   >
   >The output from Exuberant ctags is not what POSIX asks for.  Programs
   >that expect the POSIX format will thus not work, or do funny stuff.

   Again, I haven't observed that, that's exactly my point, if there is an
   issue in universal ctags output format it should be reported, but I
   haven't observed any mismatch.

I have observed the case, the POSIX format is stricter, the output
from ctags as specified by POSIX is (there are slight variants, but it
is always three fields):

  "%s\t%s\t/%s/\n", <identifier>, <filename>, <pattern>

for example, GNU Emacs ctags outputs:

  syms_of_cmds	cmds.c	/^syms_of_cmds (void)$/
 
where Exuberant (and Universal) ctags outputs:

  syms_of_cmds	cmds.c	/^syms_of_cmds (void)$/;"	f	typeref:typename:void

It is fair to fail on not being able to accept the above, or treating
the third field as one.  And one might also question how to treat a
pattern with a trailing double quote.

   >   >So really, you're suggesting to remove a standardized utility and
   >   >replace it with non-standard ones that produce incompatible output
   >   >from what is generally accepted.
   >
   >   I am suggesting to avoid the forced installation of a utility that we
   >   are not maintaining very well for another very well maintained, with
   >   more languages, support and formats.
   >
   >That is changing the point I was making, that Emacs ctags produces the
   >standard ctags output where Exuberant ctags does not.

   Universal ctags DOES generate standard ctags format (and some others
   like etags format); they actually explicitly refer to vi in the man
   page.

No, it does not.  See above; from Universal ctags from 2019.

   Exuberant is not maintained since 2011.

People still use software that is older, just that something is "not
maintained" (which can mean many things) doesn't mean that it stops
being useless.

   If there is the free and active universal ctags with a big and active
   team doing that work and supporting many format and languages, then it
   is pointless to duplicate effort and invest time on that.  Don't
   reinvent the wheel.

That is quite a dismissive comment, Emacs ctags existed long before
any of those existed (and at that point, we did not have any ctags on
GNU) so one might question who is reinventing the wheel here...