Hi,

What about the following:

#!/usr/bin/perl

use strict;
use warnings;

while (<DATA>) {
    # only check between --- show switchname --- and *****
    if ( /^-+ show switchname -+/ .. /^\*+/ ) {
        # only pick up the word between these two lines
        print "$1\n" if /(^\w+)/;
    }
}

__DATA__
 show tech-support details

-------------------- show switchname ------------------
CCC217_ANG_GREEN
******************************************************************
 show tech-support details

-------------------- show switchname ------------------
CCC218_ANG_GREEN
******************************************************************

 show tech-support details

-------------------- show switchname ------------------
CCC219_ANG_GREEN
******************************************************************
 show tech-support details

-------------------- show switchname ------------------
CCC220_ANG_GREEN
******************************************************************
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The code indicates clearly what it's about. We use .. to only look at 'blocks' in the file and then process the block lines with a regexp looking up a single word (the first word on the line actually).

---- show ---- doesn't begin with a word, and,

************** isn't a word either.

Using .. makes updating the code later on very easy. (Imagine that there are 2 lines between ---- and ****