You could simply exclude the opening parenthesis from the page capture and the closing parenthesis from the section capture like so: 

/^([^(]+)\(([^)]*)/

[download]

Here's a test with your four examples: 

$ perl -E '
    my @manpages = qw{
        ftpd(8)
        dhcp-config(5)
        Cache::Cache(3)
        Tk::widget::demo(3)
    };

    for my $line (@manpages) {
        my ($page , $section) = $line =~ /^([^(]+)\(([^)]*)/;
        say "page[$page] section[$section]";
    }
'
page[ftpd] section[8]
page[dhcp-config] section[5]
page[Cache::Cache] section[3]
page[Tk::widget::demo] section[3]

[download]

— Ken

In reply to Re: HELP! I am in regex-hell by kcott
in thread HELP! I am in regex-hell by Anonymous Monk

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