Re: GNU shellery

[Thor Lancelot Simon <tls%panix.com@localhost>]

On Sun, Oct 01, 2017 at 03:24:06PM +0000, Valery Ushakov wrote:
> 
> It doesn't work the same for multiple files.

I guess the question is whether we ought to have this if it can be made to
work the same way for multiple files.

My inclination is "yes".  It's low risk (unlike, say, modifying
the parser in the shell ;-)), and it really does cost just a hard link.
And, frankly, I like the name ("tac") -- it appeals to me for aesthetic
reasons.  Using "tail" to reverse a file has always struck me as a little
weird.  "tac" is easy to remember.

Of course, as others pointed out, GNU tac(1) has command-line options, which
this doesn't implement.  Some of them actually look moderately disruptive to
implement, making this a larger change to tail(1).  But, consider:

* For programs that need to reverse files but _only_ know how to use "tac"
  this can't make it any _worse_

* Programs with autocrud logic that picks between "tac" and "tail -r" can't
  be using any of the fancy options since tail doesn't have equivalent
  functionality.

So I think this is strictly a plus, and should be committed.

Thor