From owner-freebsd-questions@FreeBSD.ORG  Wed Nov 17 21:39:45 2010
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Date: Wed, 17 Nov 2010 21:39:45 +0000
From: Alexander Best <arundel@freebsd.org>
To: Dan Nelson <dnelson@allantgroup.com>
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	<20101117195521.GF57869@dan.emsphone.com>
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Cc: freebsd-questions@freebsd.org
Subject: Re: a question regarding proper printf(3) formating and alignment
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On Wed Nov 17 10, Dan Nelson wrote:
> In the last episode (Nov 17), Alexander Best said:
> > hi there,
> > 
> > i've looked at a lot of utilities in the bsd src tree and most of them
> > seem to be doing something like this:
> > 
> > Device          1M-blocks     Used    Avail Capacity
> > /dev/label/swapfs     10239        0    10239     0%
> > /dev/label/swap      8191        0     8191     0%
> > Total               18431        0    18431     0%
> > 
> > as you can see the header simply gets written with a number of tabs in
> > between the keywords, but then the actual output aligns differently.
> > 
> > i'd like to learn of ways formatting the header so that it aligns
> > properly, whether the device name is 10 chars long or 1000.  is there an
> > example for this somewhere in the src tree?
> 
> /bin/ls does this for the user, group, and size columns.  Note that this
> only works if you batch up your output (or take two passes over your input
> data).  I seem to remember /usr/bin/find doing this dynamically by expanding
> columns as it saw values that were larger than the previous max, but
> apparently not (I just tested it).

thanks. so looking at the /bin/ls source is probably the first i should do.

cheers.
alex

> 
> -- 
> 	Dan Nelson
> 	dnelson@allantgroup.com

-- 
a13x