my $pfx = "extindex.$name";
my $d = $self->{"$pfx.topdir"} // return;
-d $d or return;
+ if (index($d, "\n") >= 0) {
+ warn "E: `$d' must not contain `\\n'\n";
+ return;
+ }
my $es = PublicInbox::ExtSearch->new($d);
for my $k (qw(indexlevel indexsequentialshard)) {
my $v = _one_val($self, $pfx, $k) // next;