EDIT: Oops, I should have had that as .* instead of \w+. Fixed. And yes, I missed the fact that your solution was line by line instead of straight regex, holli. Shouldn't have posted a (less pretty!) duplicate, though I did arrive at it independently.

You can go ahead and ding me if you like.

----------------

Line by line processing:

use strict;
use warnings;
use Data::Dumper;

my ($key1, $key2, $val, %hash);
while (<DATA>) {
    if (($key2, $val) = m/(\w+)\((.*)\)/) {
        if ($key2 =~ /^CAL/) {
            $key1 = $val;
        }
        else {
            $hash{$key1}{$key2} = $val;
        }
    }
}

print Dumper(\%hash);

__DATA__
CALCON(test1)
{
  TYPE(U8)
  FEATURE(DCOM)
  NAM(stmin)
  LABEL(Min seperation time between CFs)
  MIN(0)
  MAX(127)
  UNITS(ms)  
}

CALCON(test2)
{
  TYPE(U16)
  FEATURE(DCOM)
  NAM(dcomc_sestmr_timeout)
  LABEL(DCOM Session Timer Timeout)
  MIN(0)
  MAX(65535)
  UNITS(ms)
}
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