while ( <FH> ) {
    if ( /^SOURCES/ && /\\$/ ) {
        $_ .= <FH>;
        redo;
        }
    elsif ( /^SOURCES/ ) {
        print;
        }
    }


##</code><code>##

my $data;
while ( <FH> ) {
    $data .= $_ if /^SOURCES/ || $data && /^\s/;
    last if $data && !/\S/;
    }
print $data;