if($1 eq 'STOCK NO') {
    $csv = $2;
}
$csv .= ",$2";

##</code><code>##

if($1 eq 'STOCK NO') {
    $csv = $2;
} else {
    $csv .= ",$2";
}

##</code><code>##

($1 eq 'STOCK NO') ? ( $csv = $2 ) : ( $csv .= ",$2" );

##</code><code>##

use strict;
use warnings;

use Text::CSV;

my $file = '782426.pl';
open(my $fh, '<', $file) or die "$file: $!";

my $csv = Text::CSV->new( { eol => "\n" } );
my @columns;

foreach ( <$fh> ) {
        chomp;
        next unless( m/^([^\.]+)\.+\s+(.*)/ );
        push(@columns, $2);
        if($1 eq 'SALES CST') { # last record of a set
                $csv->print(\*STDOUT, \@columns);
                @columns = ();
        }
}

close($fh);