".GIF" files

Gary S. Trujillo gst at gnosys.svle.ma.us
Sun Feb 24 17:44:07 AEST 1991


In <843 at argon.UUCP> ebh at argon.UUCP (Ed Horch) writes:

...

> >	cat a | b | c
> >
> >is entirely equivalent in result to:
> >
> >	b < a | c

(And, as Bruce Lilly recently observed, it's also equivalent to

	< a b | c

which David might like better, since it preserves his left-to-right
ordering.

...

> There may be a performance cost due to creating an additional
> process for "cat a", but a smart shell will know how to short-
> cut around that.

I guess it was the performance cost that concerned me most - it just
requires an extra process and takes system buffers unnecessarily.
What's this about a "smart shell"?  I've never heard of a shell that
optimizes commands.  It seems inherantly very difficult to recognize
that the two commands listed above are equivalent, since it requires
a knowledge of what cat(1) does.  What shell are we talking about here?

Actually, this discussion probably doesn't belong in the unix-pc news-
groups, but I appreciate everyone's tolerance.  And now we return you
to your regular programming...  :-)

Gary
-- 
    Gary S. Trujillo                            gst at gnosys.svle.ma.us
Somerville, Massachusetts              {wjh12,bu.edu,spdcc,ima,cdp}!gnosys!gst



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