$_ = 'ab abc abcd abcde';

/a.*b/;  # $& = 'ab abc abcd ab'
/a.*?b/; # $& = 'ab'

##</code><code>##

$src =~ s/<record.*?>/$&$new_tag/;            # No newlines matched
$src =~ s/<record[\w\s\n-="%]*?>/$&$new_tag/; # All-inclusive class?
$src =~ s/<record[^>]*>/$&$new_tag/;          # Probably best