> can make it impossible for your program *ever* to finish
If *my* pipes are incomplete until they are perfect, then they *will* never 
finish!  :-)
FWIW, I do like '| TAKE n'' to wrap up quickly and clearly; but I appreciate 
your warning.  

It's not all that often I use HOLE.  But it does seem to be where too much of 
my money goes.  :-)

Mike Walter
Aon Service Corporation
The opinions expressed herein are mine alone, not necessarily those of my 
employer.

-----Original Message-----
From: CMSTSO Pipelines Discussion List [mailto:[email protected]] On 
Behalf Of Glenn Knickerbocker
Sent: Tuesday, July 07, 2015 18:18
To: [email protected]
Subject: Re: Output to the bit bucket

On 7/7/2015 5:54 PM, Mike Walter wrote:
> 1) because by using HOLE it becomes clearer to future plumbers 
> maintaining that particular pipe that the original author specifically 
> did not intend to process output from those lookup output...
> 2) rather than having accidentally deleted needed lines which had 
> handled such lookup output during an unfortunate late-night XEDIT
> session.   :-)

However, it can also have the unintended consequence of making your program 
process more of the input than you want it to.  If you need to read a file up 
to the first occurrence of something, connecting the unused outputs to HOLE 
stages will make your pipeline read all the rest of the file, too, and do a 
bunch of useless work.

If you *need* to stop reading the input, then it's worse than just useless.  If 
you're reading from something like STARMSG that will keep a connection openfor 
as long as you keep reading, stray HOLE stages can make it impossible for your 
program *ever* to finish.

¬R

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