lib/PublicInbox/Daemon.pm | 2 ++
 lib/PublicInbox/HTTP.pm   | 2 +-
 lib/PublicInbox/HTTPD.pm  | 1 +
 lib/PublicInbox/IMAP.pm   | 2 +-
 lib/PublicInbox/NNTP.pm   | 2 +-
 lib/PublicInbox/POP3.pm   | 1 +

diff --git a/lib/PublicInbox/Daemon.pm b/lib/PublicInbox/Daemon.pm
index 0043d21eef4be44b7f391d6d1ce4099d2f091d20..bb140640c3219ec7f69b6cf9ab853039fc9fb893 100644
--- a/lib/PublicInbox/Daemon.pm
+++ b/lib/PublicInbox/Daemon.pm
@@ -134,6 +134,8 @@ 		$p = File::Spec->canonpath($p->[0]);
 		$tlsd->{$f} = $logs{$p} //= open_log_path(my $fh, $p);
 		warn "# $scheme://$addr $f=$p\n";
 	}
+	my $err = $tlsd->{err};
+	$tlsd->{warn_cb} = sub { print $err @_ }; # for local $SIG{__WARN__}
 	\%xn;
 }
 
diff --git a/lib/PublicInbox/HTTP.pm b/lib/PublicInbox/HTTP.pm
index 3d4e34995dfbd9f11749c052ec7f6766331177f5..0dba425dd6354d4925fa82b49a24ea669a16db76 100644
--- a/lib/PublicInbox/HTTP.pm
+++ b/lib/PublicInbox/HTTP.pm
@@ -69,7 +69,7 @@ }
 
 sub event_step { # called by PublicInbox::DS
 	my ($self) = @_;
-
+	local $SIG{__WARN__} = $self->{srv_env}->{'pi-httpd.warn_cb'};
 	return unless $self->flush_write && $self->{sock};
 
 	# only read more requests if we've drained the write buffer,
diff --git a/lib/PublicInbox/HTTPD.pm b/lib/PublicInbox/HTTPD.pm
index e531ee707e6d0a81cd85dd8eee6e31f399105c3f..bae7281b7979f92b483a0a26c5cc7f542f7f3464 100644
--- a/lib/PublicInbox/HTTPD.pm
+++ b/lib/PublicInbox/HTTPD.pm
@@ -47,6 +47,7 @@ 		# We also check for the truthiness of this to
 		# detect when to use async paths for slow blobs
 		'pi-httpd.async' => \&pi_httpd_async,
 		'pi-httpd.app' => $self->{app},
+		'pi-httpd.warn_cb' => $self->{warn_cb},
 	}
 }
 
diff --git a/lib/PublicInbox/IMAP.pm b/lib/PublicInbox/IMAP.pm
index 605c5e515110d1b0f1a077be70174149a78b22de..2be1b763f30a89f12e84a8c1fa0339026cf3937d 100644
--- a/lib/PublicInbox/IMAP.pm
+++ b/lib/PublicInbox/IMAP.pm
@@ -1186,7 +1186,7 @@
 # callback used by PublicInbox::DS for any (e)poll (in/out/hup/err)
 sub event_step {
 	my ($self) = @_;
-
+	local $SIG{__WARN__} = $self->{imapd}->{warn_cb};
 	return unless $self->flush_write && $self->{sock} && !$self->{long_cb};
 
 	# only read more requests if we've drained the write buffer,
diff --git a/lib/PublicInbox/NNTP.pm b/lib/PublicInbox/NNTP.pm
index 524784cb90ac3a6dfabc29f030d5e7cd32fe2704..ef01f44886203abdeaa3b07dad35226a9e7d6770 100644
--- a/lib/PublicInbox/NNTP.pm
+++ b/lib/PublicInbox/NNTP.pm
@@ -958,7 +958,7 @@
 # callback used by PublicInbox::DS for any (e)poll (in/out/hup/err)
 sub event_step {
 	my ($self) = @_;
-
+	local $SIG{__WARN__} = $self->{nntpd}->{warn_cb};
 	return unless $self->flush_write && $self->{sock} && !$self->{long_cb};
 
 	# only read more requests if we've drained the write buffer,
diff --git a/lib/PublicInbox/POP3.pm b/lib/PublicInbox/POP3.pm
index 7469922b2249f405be5a012eaa25e66c681087da..53fb2e05900b0b94f1a112189817fc12571ae0b6 100644
--- a/lib/PublicInbox/POP3.pm
+++ b/lib/PublicInbox/POP3.pm
@@ -351,6 +351,7 @@
 # callback used by PublicInbox::DS for any (e)poll (in/out/hup/err)
 sub event_step {
 	my ($self) = @_;
+	local $SIG{__WARN__} = $self->{pop3d}->{warn_cb};
 	return unless $self->flush_write && $self->{sock} && !$self->{long_cb};
 
 	# only read more requests if we've drained the write buffer,