There are many alternatives. Here is one way that keeps the overall layout of the file:

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

foreach my $file (glob("*.ATT")) {
    open(my $fh, '<', $file) or die "$file: $!";
    my $content = do { local $/; <$fh> };
    close($fh);

    my ( $page_id ) = $content =~ m/^page_id=(.*)/m;
    my ( $site_code ) = $content =~ m/^site_code=(.*)/m;
    my ( $subject_id ) = $content =~ m/^subject_id=(.*)/m;
    my ( $page_description ) = $content =~ m/^page_description=(.*)/m;

    next if(
        $page_id =~ m/(^\s*$|\?)/ or
        $site_code =~ m/(^\s*$|\?)/ or
        $subject_id =~ m/(^\s*$|\?)/
    );

    $page_description .= "some text - $page_id";

    $content =~ s/^page_description=.*/page_description=$page_descript
+ion/m;

    print "$content";
}

[download]

In this case, the entire file content is read into a single string (slurped) then pattern matching and substitution are used to extract data and modify the description without chaning the overall layout. The result is:

OBJECT=(removed)
page_id=#### (usually 3-5 digits)
page_description=some text - #### (usually 3-5 digits)
product=(removed)
study_number=(removed)
content_provider=(removed)
site_code=###
subject_id=#########
CONTENT=test.pdf
SAVE

[download]

In reply to Re^3: Perl noob is lost by ig
in thread Perl noob is lost by sensesfail

Title:
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