A friend was bemoaning a few Linux quota tools that gave hard-to-parse output. It would output a header line, followed by a number of lines of data. An example: 
Filesystem  blocks   quota   limit   grace   files ...
 /dev/hdd3   26320   46080   51200            1521 ...
 /dev/hdd4   26320           51200            1060 ...

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My friend's problem was trying to deal with the "empty" columns in the data lines. When just using a naive split(), the empty columns would disappear, throwing off the count. 
# controlled search-and-replace to insert column markers
# using the header line as a guide to where the columns lie

$headers = <>;
$headers =~ s/(\S)\s/$1\#/g;
while (<>)
{
  s/\s/ (substr($headers, pos(), 1) eq '#')? '#' : ' ' /eg;
  @_ = split /\s*\#\s*/;
  # @_ now has true columns ready for whitespace trimming
}

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In reply to parsing sloppy text from columns by halley

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