Well, lets assume the original programmer was considerate and used meaningful variable names. If the things with the "$parm" are of this style: 
  if ( $parm{something} eq 'a value' ) {
      #do something
  }

[download]
Then the $parm is really a hash (see page 50 onwards in your Camel). You may find that a number of different values being passed to the program are grouped in the %parm hash (note the name now starting with a percent sign). So somewhere at the start of the program could be a routine to read the command line parameters, and set the key / value pairs of a hash.

Another good Perl book is the "Perl Cookbook" (also called the Ram book because of the funky big horn sheep on the cover). Jam packed full of real life examples - this shows you how you actually use all those cool things written about in the Camel.

In reply to Re: st00pid, remedial by Maclir
in thread st00pid, remedial by hackadelic

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.