shell pipeline to reverse the order of lines.

[Oliver Laumann]

In article <19079 at rpp386.cactus.org> jfh at rpp386.cactus.org (John F Haugh II) writes:
> >Considering that the `tail' command under vanilla BSD (at least 4.2 and
> >4.3 BSD) has this `feature' I wouldn't call it non-standard.  After all,
> >`tail' is a BSD command.
> 
> What would you prefer to call a feature which does not exist on all
> systems that have the command? 

A vendor is free to put a version of `ls' on their UNIX port that
doesn't support the -l option any longer.  Does this make `ls -l'
non-standard?  Certainly not.

> What would you prefer to call a command which may not exist on all systems?

The fact that it may not exist on *all* systems is irrelevant.  I'm sure
that for almost any UNIX command (except maybe date, ls, etc.) you will
be able to find a system where this command does not exist.

> As for being a ``BSD'' feature, I've yet to see a UNIX system without
> the command,

Why do you think `tail' is under /usr/ucb (on those systems that have
a /usr/ucb)?  If the commands under /usr/ucb are not BSD commands,
then what *is* a BSD command?

--
Oliver Laumann    net at tub.cs.tu-berlin.de  net at tub.UUCP  net at pogo.ai.mit.edu