sd-bus: Add sd_bus_is_server + sd_bus_set/is_bus_client docs

Fix formatting in in resolved.conf(5) and nss-resolve(8)

man/custom-html.xsl

@@ -1,9 +1,5 @@
 <?xml version='1.0'?> <!--*-nxml-*-->
-
+<!-- SPDX-License-Identifier: LGPL-2.1+ -->
-<!--
-  SPDX-License-Identifier: LGPL-2.1+
-
--->
 
 <xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="1.0">
 
@@ -96,6 +92,21 @@
   </a>
 </xsl:template>
 
+<xsl:template match="citerefentry[@project='debian']">
+  <a>
+    <xsl:attribute name="href">
+      <xsl:text>https://manpages.debian.org/unstable/</xsl:text>
+      <xsl:value-of select="refentrytitle"/>
+      <xsl:text>/</xsl:text>
+      <xsl:value-of select="refentrytitle"/>
+      <xsl:text>.</xsl:text>
+      <xsl:value-of select="manvolnum"/>
+      <xsl:text>.en.html</xsl:text>
+    </xsl:attribute>
+    <xsl:call-template name="inline.charseq"/>
+  </a>
+</xsl:template>
+
 <xsl:template match="citerefentry[@project='freebsd']">
   <a>
     <xsl:attribute name="href">

man/resolvectl.xml

@@ -288,17 +288,27 @@
   </refsect1>
 
   <refsect1>
-    <title>Compatibility with <citerefentry><refentrytitle>resolvconf</refentrytitle><manvolnum>8</manvolnum></citerefentry></title>
+    <title>Compatibility with
+    <citerefentry project="debian"><refentrytitle>resolvconf</refentrytitle><manvolnum>8</manvolnum></citerefentry></title>
 
     <para><command>resolvectl</command> is a multi-call binary. When invoked as <literal>resolvconf</literal>
     (generally achieved by means of a symbolic link of this name to the <command>resolvectl</command> binary) it
-    is run in a limited <citerefentry><refentrytitle>resolvconf</refentrytitle><manvolnum>8</manvolnum></citerefentry>
+    is run in a limited
+    <citerefentry project="debian"><refentrytitle>resolvconf</refentrytitle><manvolnum>8</manvolnum></citerefentry>
     compatibility mode. It accepts mostly the same arguments and pushes all data into
     <citerefentry><refentrytitle>systemd-resolved.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
     similar to how <option>dns</option> and <option>domain</option> commands operate. Note that
     <command>systemd-resolved.service</command> is the only supported backend, which is different from other
-    implementations of this command. Note that not all operations supported by other implementations are supported
+    implementations of this command.</para>
-    natively. Specifically:</para>
+
+    <para><filename>/etc/resolv.conf</filename> will only be updated with servers added with this command
+    when <filename>/etc/resolv.conf</filename> is a symlink to
+    <filename>/run/systemd/resolve/resolv.conf</filename>, and not a static file. See the discussion of
+    <filename>/etc/resolv.conf</filename> handling in
+    <citerefentry><refentrytitle>systemd-resolved.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>.
+    </para>
+
+    <para>Not all operations supported by other implementations are supported natively. Specifically:</para>
 
     <variablelist>
       <varlistentry>
@@ -359,7 +369,9 @@
 
     </variablelist>
 
-    <para>See <citerefentry><refentrytitle>resolvconf</refentrytitle><manvolnum>8</manvolnum></citerefentry> for details on this command line options.</para>
+    <para>See
+    <citerefentry project="debian"><refentrytitle>resolvconf</refentrytitle><manvolnum>8</manvolnum></citerefentry>
+    for details on those command line options.</para>
   </refsect1>
 
   <refsect1>

man/resolved.conf.xml

@@ -234,11 +234,11 @@
 
       <varlistentry>
         <term><varname>Cache=</varname></term>
-        <listitem><para>Takes a boolean or <literal>no-negative</literal> as argument. If <literal>yes</literal> (the default), resolving a domain name
+        <listitem><para>Takes a boolean or <literal>no-negative</literal> as argument. If
-        which already got queried earlier will return the previous result as long as it is still valid, and thus does
+        <literal>yes</literal> (the default), resolving a domain name which already got queried earlier will
-        not result in a new network request. Be aware that turning off caching comes at a performance penalty, which
+        return the previous result as long as it is still valid, and thus does not result in a new network
-        is particularly high when DNSSEC is used.</para>
+        request. Be aware that turning off caching comes at a performance penalty, which is particularly high
-        If <literal>no-negative</literal>, only positive answers are cached.
+        when DNSSEC is used. If <literal>no-negative</literal>, only positive answers are cached.</para>
 
         <para>Note that caching is turned off implicitly if the configured DNS server is on a host-local IP address
         (such as 127.0.0.1 or ::1), in order to avoid duplicate local caching.</para></listitem>

man/rules/meson.build

@@ -398,7 +398,13 @@ manpages = [
    'sd_bus_set_propertyv'],
   ''],
  ['sd_bus_set_sender', '3', ['sd_bus_get_sender'], ''],
- ['sd_bus_set_server', '3', ['sd_bus_get_bus_id'], ''],
+ ['sd_bus_set_server',
+  '3',
+  ['sd_bus_get_bus_id',
+   'sd_bus_is_bus_client',
+   'sd_bus_is_server',
+   'sd_bus_set_bus_client'],
+  ''],
  ['sd_bus_set_watch_bind', '3', ['sd_bus_get_watch_bind'], ''],
  ['sd_bus_slot_get_bus',
   '3',

man/sd-bus.xml

@@ -80,6 +80,8 @@
 <citerefentry><refentrytitle>sd_bus_get_fd</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
 <citerefentry><refentrytitle>sd_bus_get_method_call_timeout</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
 <citerefentry><refentrytitle>sd_bus_get_n_queued_read</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+<citerefentry><refentrytitle>sd_bus_is_bus_client</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+<citerefentry><refentrytitle>sd_bus_is_server</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
 <citerefentry><refentrytitle>sd_bus_message_append</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
 <citerefentry><refentrytitle>sd_bus_message_append_array</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
 <citerefentry><refentrytitle>sd_bus_message_append_basic</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
@@ -125,6 +127,7 @@
 <citerefentry><refentrytitle>sd_bus_set_property</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
 <citerefentry><refentrytitle>sd_bus_set_propertyv</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
 <citerefentry><refentrytitle>sd_bus_set_sender</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+<citerefentry><refentrytitle>sd_bus_set_bus_client</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
 <citerefentry><refentrytitle>sd_bus_set_server</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
 <citerefentry><refentrytitle>sd_bus_set_watch_bind</refentrytitle><manvolnum>3</manvolnum></citerefentry>
 <citerefentry><refentrytitle>sd_bus_set_close_on_exit</refentrytitle><manvolnum>3</manvolnum></citerefentry>,

man/sd_bus_get_current_handler.xml

@@ -55,13 +55,12 @@
 
     <para>Whenever sd-bus is about to invoke a user-supplied callback function, it stores the
     current callback, D-Bus message, slot and userdata pointer and allows these to be queried via
-    these <function>sd_bus_get_current_handler()</function>,
+    <function>sd_bus_get_current_handler()</function>,
     <function>sd_bus_get_current_message()</function>,
     <function>sd_bus_get_current_slot()</function> and
     <function>sd_bus_get_current_userdata()</function>, respectively. If <parameter>bus</parameter>
     cannot be resolved or if execution does not reside in a user-supplied callback of
-    <parameter>bus</parameter> when calling any of these functions, they return
+    <parameter>bus</parameter>, these functions return <constant>NULL</constant>.</para>
-    <constant>NULL</constant>.</para>
   </refsect1>
 
   <refsect1>

man/sd_bus_set_server.xml

@@ -18,9 +18,12 @@
 
   <refnamediv>
     <refname>sd_bus_set_server</refname>
+    <refname>sd_bus_is_server</refname>
     <refname>sd_bus_get_bus_id</refname>
+    <refname>sd_bus_set_bus_client</refname>
+    <refname>sd_bus_is_bus_client</refname>
 
-    <refpurpose>Configure server mode for a bus object</refpurpose>
+    <refpurpose>Configure direct connection mode for a bus object</refpurpose>
   </refnamediv>
 
   <refsynopsisdiv>
@@ -34,11 +37,27 @@
         <paramdef>sd_id128_t <parameter>id</parameter></paramdef>
       </funcprototype>
 
+      <funcprototype>
+        <funcdef>int <function>sd_bus_is_server</function></funcdef>
+        <paramdef>sd_bus *<parameter>bus</parameter></paramdef>
+      </funcprototype>
+
       <funcprototype>
         <funcdef>int <function>sd_bus_get_bus_id</function></funcdef>
         <paramdef>sd_bus *<parameter>bus</parameter></paramdef>
         <paramdef>sd_id128_t *<parameter>id</parameter></paramdef>
       </funcprototype>
+
+      <funcprototype>
+        <funcdef>int <function>sd_bus_set_bus_client</function></funcdef>
+        <paramdef>sd_bus *<parameter>bus</parameter></paramdef>
+        <paramdef>int <parameter>b</parameter></paramdef>
+      </funcprototype>
+
+      <funcprototype>
+        <funcdef>int <function>sd_bus_is_bus_client</function></funcdef>
+        <paramdef>sd_bus *<parameter>bus</parameter></paramdef>
+      </funcprototype>
     </funcsynopsis>
   </refsynopsisdiv>
 
@@ -55,16 +74,44 @@
     <citerefentry><refentrytitle>sd_id128_randomize</refentrytitle><manvolnum>3</manvolnum></citerefentry>
     can be used to generate a random id instead.</para>
 
+    <para><function>sd_bus_is_server()</function> returns whether the server mode is enabled for
+    the given bus object.</para>
+
     <para><function>sd_bus_get_bus_id()</function> stores the D-Bus server id configured using
     <function>sd_bus_set_server()</function> (for server bus objects) or received during
     D-Bus authentication (for client bus objects) in <parameter>id</parameter>.</para>
+
+    <para><function>sd_bus_set_bus_client()</function> configures the bus object as a D-Bus daemon
+    client. <parameter>b</parameter> enables/disables the client mode. If zero, the client mode is
+    disabled and the bus object should connect directly to a D-Bus server. Otherwise, the client
+    mode is enabled and the bus object should connect to a D-Bus daemon. When connecting to an
+    existing bus using any of the functions in the
+    <citerefentry><refentrytitle>sd_bus_open</refentrytitle><manvolnum>3</manvolnum></citerefentry>
+    family of functions or any of the functions in the
+    <citerefentry><refentrytitle>sd_bus_default</refentrytitle><manvolnum>3</manvolnum></citerefentry>
+    family of functions, the bus object is automatically configured as a bus client. However, when
+    connecting to a D-Bus daemon by calling
+    <citerefentry><refentrytitle>sd_bus_set_address</refentrytitle><manvolnum>3</manvolnum></citerefentry>
+    followed by
+    <citerefentry><refentrytitle>sd_bus_start</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+    the bus object should be manually configured as a bus client using
+    <function>sd_bus_set_bus_client()</function>. By default, a bus object is not configured as a
+    D-Bus daemon client.</para>
+
+    <para><function>sd_bus_is_bus_client()</function> returns whether the client mode is
+    enabled/disabled for the given bus object.</para>
   </refsect1>
 
   <refsect1>
     <title>Return Value</title>
 
-    <para>On success, these functions return a non-negative integer. On failure, they return a
+    <para>On success, <function>sd_bus_set_server()</function>,
-    negative errno-style error code.</para>
+    <function>sd_bus_get_bus_id()</function> and <function>sd_bus_set_bus_client()</function> return
+    a non-negative integer. On failure, they return a negative errno-style error code.</para>
+
+    <para><function>sd_bus_is_server()</function> and <function>sd_bus_is_bus_client()</function>
+    return 1 when the server or client mode is enabled, respectively. Otherwise, they return 0.
+    </para>
 
     <refsect2>
       <title>Errors</title>

man/systemd-resolved.service.xml

@@ -29,9 +29,10 @@
   <refsect1>
     <title>Description</title>
 
-    <para><command>systemd-resolved</command> is a system service that provides network name resolution to local
+    <para><command>systemd-resolved</command> is a system service that provides network name resolution to
-    applications. It implements a caching and validating DNS/DNSSEC stub resolver, as well as an LLMNR and MulticastDNS
+    local applications. It implements a caching and validating DNS/DNSSEC stub resolver, as well as an LLMNR
-    resolver and responder. Local applications may submit network name resolution requests via three interfaces:</para>
+    and MulticastDNS resolver and responder. Local applications may submit network name resolution requests
+    via three interfaces:</para>
 
     <itemizedlist>
       <listitem><para>The native, fully-featured API <command>systemd-resolved</command> exposes on the bus,
@@ -42,144 +43,149 @@
       necessary for supporting link-local networking).</para></listitem>
 
       <listitem><para>The glibc
-      <citerefentry project='man-pages'><refentrytitle>getaddrinfo</refentrytitle><manvolnum>3</manvolnum></citerefentry> API as defined
+      <citerefentry project='man-pages'><refentrytitle>getaddrinfo</refentrytitle><manvolnum>3</manvolnum></citerefentry>
-      by <ulink url="https://tools.ietf.org/html/rfc3493">RFC3493</ulink> and its related resolver functions,
+      API as defined by <ulink url="https://tools.ietf.org/html/rfc3493">RFC3493</ulink> and its related
-      including <citerefentry project='man-pages'><refentrytitle>gethostbyname</refentrytitle><manvolnum>3</manvolnum></citerefentry>. This
+      resolver functions, including
-      API is widely supported, including beyond the Linux platform. In its current form it does not expose DNSSEC
+      <citerefentry project='man-pages'><refentrytitle>gethostbyname</refentrytitle><manvolnum>3</manvolnum></citerefentry>.
-      validation status information however, and is synchronous only. This API is backed by the glibc Name Service
+      This API is widely supported, including beyond the Linux platform. In its current form it does not
-      Switch (<citerefentry project='man-pages'><refentrytitle>nss</refentrytitle><manvolnum>5</manvolnum></citerefentry>). Usage of the
+      expose DNSSEC validation status information however, and is synchronous only. This API is backed by the
-      glibc NSS module <citerefentry><refentrytitle>nss-resolve</refentrytitle><manvolnum>8</manvolnum></citerefentry>
+      glibc Name Service Switch
-      is required in order to allow glibc's NSS resolver functions to resolve host names via
+      (<citerefentry project='man-pages'><refentrytitle>nss</refentrytitle><manvolnum>5</manvolnum></citerefentry>).
+      Usage of the glibc NSS module
+      <citerefentry><refentrytitle>nss-resolve</refentrytitle><manvolnum>8</manvolnum></citerefentry> is
+      required in order to allow glibc's NSS resolver functions to resolve host names via
       <command>systemd-resolved</command>.</para></listitem>
 
-      <listitem><para>Additionally, <command>systemd-resolved</command> provides a local DNS stub listener on IP
+      <listitem><para>Additionally, <command>systemd-resolved</command> provides a local DNS stub listener on
-      address 127.0.0.53 on the local loopback interface. Programs issuing DNS requests directly, bypassing any local
+      IP address 127.0.0.53 on the local loopback interface. Programs issuing DNS requests directly,
-      API may be directed to this stub, in order to connect them to <command>systemd-resolved</command>. Note however
+      bypassing any local API may be directed to this stub, in order to connect them to
-      that it is strongly recommended that local programs use the glibc NSS or bus APIs instead (as described above),
+      <command>systemd-resolved</command>. Note however that it is strongly recommended that local programs
-      as various network resolution concepts (such as link-local addressing, or LLMNR Unicode domains) cannot be mapped
+      use the glibc NSS or bus APIs instead (as described above), as various network resolution concepts
-      to the unicast DNS protocol.</para></listitem>
+      (such as link-local addressing, or LLMNR Unicode domains) cannot be mapped to the unicast DNS
+      protocol.</para></listitem>
     </itemizedlist>
 
     <para>The DNS servers contacted are determined from the global settings in
     <filename>/etc/systemd/resolved.conf</filename>, the per-link static settings in
     <filename>/etc/systemd/network/*.network</filename> files (in case
-    <citerefentry><refentrytitle>systemd-networkd.service</refentrytitle><manvolnum>8</manvolnum></citerefentry> is
+    <citerefentry><refentrytitle>systemd-networkd.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>
-    used), the per-link dynamic settings received over DHCP, user request made via
+    is used), the per-link dynamic settings received over DHCP, user request made via
-    <citerefentry><refentrytitle>resolvectl</refentrytitle><manvolnum>1</manvolnum></citerefentry>, and any DNS server
+    <citerefentry><refentrytitle>resolvectl</refentrytitle><manvolnum>1</manvolnum></citerefentry>, and any
-    information made available by other system services. See
+    DNS server information made available by other system services. See
     <citerefentry><refentrytitle>resolved.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry> and
-    <citerefentry><refentrytitle>systemd.network</refentrytitle><manvolnum>5</manvolnum></citerefentry> for details
+    <citerefentry><refentrytitle>systemd.network</refentrytitle><manvolnum>5</manvolnum></citerefentry> for
-    about systemd's own configuration files for DNS servers. To improve compatibility,
+    details about systemd's own configuration files for DNS servers. To improve compatibility,
-    <filename>/etc/resolv.conf</filename> is read in order to discover configured system DNS servers, but only if it is
+    <filename>/etc/resolv.conf</filename> is read in order to discover configured system DNS servers, but
-    not a symlink to <filename>/run/systemd/resolve/stub-resolv.conf</filename>,
+    only if it is not a symlink to <filename>/run/systemd/resolve/stub-resolv.conf</filename>,
-    <filename>/usr/lib/systemd/resolv.conf</filename> or <filename>/run/systemd/resolve/resolv.conf</filename> (see
+    <filename>/usr/lib/systemd/resolv.conf</filename> or
-    below).</para>
+    <filename>/run/systemd/resolve/resolv.conf</filename> (see below).</para>
 
   </refsect1>
 
   <refsect1>
     <title>Synthetic Records</title>
 
-    <para><command>systemd-resolved</command> synthesizes DNS resource records (RRs) for the following cases:</para>
+    <para><command>systemd-resolved</command> synthesizes DNS resource records (RRs) for the following
+    cases:</para>
 
     <itemizedlist>
-      <listitem><para>The local, configured hostname is resolved to
+      <listitem><para>The local, configured hostname is resolved to all locally configured IP addresses
-      all locally configured IP addresses ordered by their scope, or
+      ordered by their scope, or — if none are configured — the IPv4 address 127.0.0.2 (which is on the local
-      — if none are configured — the IPv4 address 127.0.0.2 (which
+      loopback) and the IPv6 address ::1 (which is the local host).</para></listitem>
-      is on the local loopback) and the IPv6 address ::1 (which is the
-      local host).</para></listitem>
 
-      <listitem><para>The hostnames <literal>localhost</literal> and
+      <listitem><para>The hostnames <literal>localhost</literal> and <literal>localhost.localdomain</literal>
-      <literal>localhost.localdomain</literal> (as well as any hostname
+      (as well as any hostname ending in <literal>.localhost</literal> or
-      ending in <literal>.localhost</literal> or <literal>.localhost.localdomain</literal>)
+      <literal>.localhost.localdomain</literal>) are resolved to the IP addresses 127.0.0.1 and ::1.
-      are resolved to the IP addresses 127.0.0.1 and ::1.</para></listitem>
+      </para></listitem>
 
-      <listitem><para>The hostname <literal>_gateway</literal> is
+      <listitem><para>The hostname <literal>_gateway</literal> is resolved to all current default routing
-      resolved to all current default routing gateway addresses,
+      gateway addresses, ordered by their metric. This assigns a stable hostname to the current gateway,
-      ordered by their metric. This assigns a stable hostname to the
+      useful for referencing it independently of the current network configuration state.</para></listitem>
-      current gateway, useful for referencing it independently of the
-      current network configuration state.</para></listitem>
 
-      <listitem><para>The mappings defined in <filename>/etc/hosts</filename> are resolved
+      <listitem><para>The mappings defined in <filename>/etc/hosts</filename> are resolved to their
-      to their configured addresses and back, but they will not affect lookups for
+      configured addresses and back, but they will not affect lookups for non-address types (like MX).
-      non-address types (like MX).</para></listitem>
+      </para></listitem>
     </itemizedlist>
   </refsect1>
 
   <refsect1>
     <title>Protocols and Routing</title>
 
-    <para>Lookup requests are routed to the available DNS servers, LLMNR and MulticastDNS interfaces according to the
+    <para>Lookup requests are routed to the available DNS servers, LLMNR and MulticastDNS interfaces
-    following rules:</para>
+    according to the following rules:</para>
 
     <itemizedlist>
-      <listitem><para>Lookups for the special hostname <literal>localhost</literal> are never routed to the network. (A
+      <listitem><para>Lookups for the special hostname <literal>localhost</literal> are never routed to the
-      few other, special domains are handled the same way.)</para></listitem>
+      network. (A few other, special domains are handled the same way.)</para></listitem>
 
-      <listitem><para>Single-label names are routed to all local interfaces capable of IP multicasting, using the LLMNR
+      <listitem><para>Single-label names are routed to all local interfaces capable of IP multicasting, using
-      protocol. Lookups for IPv4 addresses are only sent via LLMNR on IPv4, and lookups for IPv6 addresses are only
+      the LLMNR protocol. Lookups for IPv4 addresses are only sent via LLMNR on IPv4, and lookups for IPv6
-      sent via LLMNR on IPv6. Lookups for the locally configured host name and the <literal>_gateway</literal> host
+      addresses are only sent via LLMNR on IPv6. Lookups for the locally configured host name and the
-      name are never routed to LLMNR.</para></listitem>
+      <literal>_gateway</literal> host name are never routed to LLMNR.</para></listitem>
 
-      <listitem><para>Multi-label names with the domain suffix <literal>.local</literal> are routed to all local
+      <listitem><para>Multi-label names with the domain suffix <literal>.local</literal> are routed to all
-      interfaces capable of IP multicasting, using the MulticastDNS protocol. As with LLMNR IPv4 address lookups are
+      local interfaces capable of IP multicasting, using the MulticastDNS protocol. As with LLMNR IPv4
-      sent via IPv4 and IPv6 address lookups are sent via IPv6.</para></listitem>
+      address lookups are sent via IPv4 and IPv6 address lookups are sent via IPv6.</para></listitem>
 
-      <listitem><para>Other multi-label names are routed to all local interfaces that have a DNS server configured,
+      <listitem><para>Other multi-label names are routed to all local interfaces that have a DNS server
-      plus the globally configured DNS server if there is one. Address lookups from the link-local address range are
+      configured, plus the globally configured DNS server if there is one. Address lookups from the
-      never routed to DNS. Note that by default lookups for domains with the <literal>.local</literal> suffix are not
+      link-local address range are never routed to DNS. Note that by default lookups for domains with the
-      routed to DNS servers, unless the domain is specified explicitly as routing or search domain for the DNS server
+      <literal>.local</literal> suffix are not routed to DNS servers, unless the domain is specified
-      and interface. This means that on networks where the <literal>.local</literal> domain is defined in a
+      explicitly as routing or search domain for the DNS server and interface. This means that on networks
-      site-specific DNS server, explicit search or routing domains need to be configured to make lookups within this
+      where the <literal>.local</literal> domain is defined in a site-specific DNS server, explicit search or
-      DNS domain work. Note that today it's generally recommended to avoid defining <literal>.local</literal> in a DNS
+      routing domains need to be configured to make lookups within this DNS domain work. Note that today it's
-      server, as <ulink url="https://tools.ietf.org/html/rfc6762">RFC6762</ulink> reserves this domain for exclusive
+      generally recommended to avoid defining <literal>.local</literal> in a DNS server, as <ulink
+      url="https://tools.ietf.org/html/rfc6762">RFC6762</ulink> reserves this domain for exclusive
       MulticastDNS use.</para></listitem>
     </itemizedlist>
 
-    <para>If lookups are routed to multiple interfaces, the first
+    <para>If lookups are routed to multiple interfaces, the first successful response is returned (thus
-    successful response is returned (thus effectively merging the
+    effectively merging the lookup zones on all matching interfaces). If the lookup failed on all interfaces,
-    lookup zones on all matching interfaces). If the lookup failed on
+    the last failing response is returned.</para>
-    all interfaces, the last failing response is returned.</para>
 
-    <para>Routing of lookups may be influenced by configuring per-interface domain names and other settings. See
+    <para>Routing of lookups may be influenced by configuring per-interface domain names and other
+    settings. See
     <citerefentry><refentrytitle>systemd.network</refentrytitle><manvolnum>5</manvolnum></citerefentry> and
-    <citerefentry><refentrytitle>resolvectl</refentrytitle><manvolnum>1</manvolnum></citerefentry> for details. The
+    <citerefentry><refentrytitle>resolvectl</refentrytitle><manvolnum>1</manvolnum></citerefentry> for
-    following query routing logic applies for unicast DNS traffic:</para>
+    details. The following query routing logic applies for unicast DNS traffic:</para>
 
     <itemizedlist>
-      <listitem><para>If a name to look up matches (that is: is equal to or has as suffix) any of the configured search
+      <listitem><para>If a name to look up matches (that is: is equal to or has as suffix) any of the
-      or route-only domains of any link (or the globally configured DNS settings), the "best matching"
+      configured search or route-only domains of any link (or the globally configured DNS settings), the
-      search/route-only domain is determined: the matching one with the most labels. The query is then sent to all DNS
+      "best matching" search/route-only domain is determined: the matching one with the most labels. The
-      servers of any links or the globally configured DNS servers associated with this "best matching"
+      query is then sent to all DNS servers of any links or the globally configured DNS servers associated
-      search/route-only domain. (Note that more than one link might have this same "best matching" search/route-only
+      with this "best matching" search/route-only domain. (Note that more than one link might have this same
-      domain configured, in which case the query is sent to all of them in parallel).</para></listitem>
+      "best matching" search/route-only domain configured, in which case the query is sent to all of them in
+      parallel).</para></listitem>
 
-      <listitem><para>If a query does not match any configured search/route-only domain (neither per-link nor global),
+      <listitem><para>If a query does not match any configured search/route-only domain (neither per-link nor
-      it is sent to all DNS servers that are configured on links with the "DNS default route" option set, as well as
+      global), it is sent to all DNS servers that are configured on links with the "DNS default route" option
-      the globally configured DNS server.</para></listitem>
+      set, as well as the globally configured DNS server.</para></listitem>
 
-      <listitem><para>If there is no link configured as "DNS default route" and no global DNS server configured, the
+      <listitem><para>If there is no link configured as "DNS default route" and no global DNS server
-      compiled-in fallback DNS server is used.</para></listitem>
+      configured, the compiled-in fallback DNS server is used.</para></listitem>
 
-      <listitem><para>Otherwise the query is failed as no suitable DNS servers could be determined.</para></listitem>
+      <listitem><para>Otherwise the query is failed as no suitable DNS servers could be determined.
+      </para></listitem>
     </itemizedlist>
 
-    <para>The "DNS default route" option is a boolean setting configurable with <command>resolvectl</command> or in
+    <para>The "DNS default route" option is a boolean setting configurable with <command>resolvectl</command>
-    <filename>.network</filename> files. If not set, it is implicitly determined based on the configured DNS domains
+    or in <filename>.network</filename> files. If not set, it is implicitly determined based on the
-    for a link: if there's any route-only domain (not matching <literal>~.</literal>) it defaults to false, otherwise
+    configured DNS domains for a link: if there's any route-only domain (not matching <literal>~.</literal>)
-    to true.</para>
+    it defaults to false, otherwise to true.</para>
 
     <para>Effectively this means: in order to preferably route all DNS queries not explicitly matched by
-    search/route-only domain configuration to a specific link, configure a <literal>~.</literal> route-only domain on
+    search/route-only domain configuration to a specific link, configure a <literal>~.</literal> route-only
-    it. This will ensure that other links will not be considered for the queries (unless they too carry such a
+    domain on it. This will ensure that other links will not be considered for the queries (unless they too
-    route-only domain). In order to route all such DNS queries to a specific link only in case no other link is
+    carry such a route-only domain). In order to route all such DNS queries to a specific link only in case
-    preferable, then set the "DNS default route" option for the link to true, and do not configure a
+    no other link is preferable, then set the "DNS default route" option for the link to true, and do not
-    <literal>~.</literal> route-only domain on it. Finally, in order to ensure that a specific link never receives any
+    configure a <literal>~.</literal> route-only domain on it. Finally, in order to ensure that a specific
-    DNS traffic not matching any of its configured search/route-only domains, set the "DNS default route" option for it
+    link never receives any DNS traffic not matching any of its configured search/route-only domains, set the
-    to false.</para>
+    "DNS default route" option for it to false.</para>
 
-    <para>See the <ulink url="https://www.freedesktop.org/wiki/Software/systemd/resolved"> resolved D-Bus API
+    <para>See the <ulink url="https://www.freedesktop.org/wiki/Software/systemd/resolved">resolved D-Bus API
-    Documentation</ulink> for information about the APIs <filename>systemd-resolved</filename> provides.</para>
+    Documentation</ulink> for information about the APIs <filename>systemd-resolved</filename> provides.
+    </para>
   </refsect1>
 
   <refsect1>
@@ -191,40 +197,41 @@
 
     <itemizedlist>
       <listitem><para><command>systemd-resolved</command> maintains the
-      <filename>/run/systemd/resolve/stub-resolv.conf</filename> file for compatibility with traditional Linux
+      <filename>/run/systemd/resolve/stub-resolv.conf</filename> file for compatibility with traditional
-      programs. This file may be symlinked from <filename>/etc/resolv.conf</filename>. This file lists the 127.0.0.53
+      Linux programs. This file may be symlinked from <filename>/etc/resolv.conf</filename>. This file lists
-      DNS stub (see above) as the only DNS server. It also contains a list of search domains that are in use by
+      the 127.0.0.53 DNS stub (see above) as the only DNS server. It also contains a list of search domains
-      systemd-resolved. The list of search domains is always kept up-to-date. Note that
+      that are in use by systemd-resolved. The list of search domains is always kept up-to-date. Note that
-      <filename>/run/systemd/resolve/stub-resolv.conf</filename> should not be used directly by applications, but only
+      <filename>/run/systemd/resolve/stub-resolv.conf</filename> should not be used directly by applications,
-      through a symlink from <filename>/etc/resolv.conf</filename>. This file may be symlinked from
+      but only through a symlink from <filename>/etc/resolv.conf</filename>. This file may be symlinked from
-      <filename>/etc/resolv.conf</filename> in order to connect all local clients that bypass local DNS APIs to
+      <filename>/etc/resolv.conf</filename> in order to connect all local clients that bypass local DNS APIs
-      <command>systemd-resolved</command> with correct search domains settings. This mode of operation is
+      to <command>systemd-resolved</command> with correct search domains settings. This mode of operation is
       recommended.</para></listitem>
 
       <listitem><para>A static file <filename>/usr/lib/systemd/resolv.conf</filename> is provided that lists
       the 127.0.0.53 DNS stub (see above) as only DNS server. This file may be symlinked from
-      <filename>/etc/resolv.conf</filename> in order to connect all local clients that bypass local DNS APIs to
+      <filename>/etc/resolv.conf</filename> in order to connect all local clients that bypass local DNS APIs
-      <command>systemd-resolved</command>. This file does not contain any search domains.</para></listitem>
+      to <command>systemd-resolved</command>. This file does not contain any search domains.
+      </para></listitem>
 
       <listitem><para><command>systemd-resolved</command> maintains the
       <filename>/run/systemd/resolve/resolv.conf</filename> file for compatibility with traditional Linux
-      programs. This file may be symlinked from <filename>/etc/resolv.conf</filename> and is always kept up-to-date,
+      programs. This file may be symlinked from <filename>/etc/resolv.conf</filename> and is always kept
-      containing information about all known DNS servers. Note the file format's limitations: it does not know a
+      up-to-date, containing information about all known DNS servers. Note the file format's limitations: it
-      concept of per-interface DNS servers and hence only contains system-wide DNS server definitions. Note that
+      does not know a concept of per-interface DNS servers and hence only contains system-wide DNS server
-      <filename>/run/systemd/resolve/resolv.conf</filename> should not be used directly by applications, but only
+      definitions. Note that <filename>/run/systemd/resolve/resolv.conf</filename> should not be used
-      through a symlink from <filename>/etc/resolv.conf</filename>. If this mode of operation is used local clients
+      directly by applications, but only through a symlink from <filename>/etc/resolv.conf</filename>. If
-      that bypass any local DNS API will also bypass <command>systemd-resolved</command> and will talk directly to the
+      this mode of operation is used local clients that bypass any local DNS API will also bypass
-      known DNS servers.</para> </listitem>
+      <command>systemd-resolved</command> and will talk directly to the known DNS servers.</para></listitem>
 
-      <listitem><para>Alternatively, <filename>/etc/resolv.conf</filename> may be managed by other packages, in which
+      <listitem><para>Alternatively, <filename>/etc/resolv.conf</filename> may be managed by other packages,
-      case <command>systemd-resolved</command> will read it for DNS configuration data. In this mode of operation
+      in which case <command>systemd-resolved</command> will read it for DNS configuration data. In this mode
-      <command>systemd-resolved</command> is consumer rather than provider of this configuration
+      of operation <command>systemd-resolved</command> is consumer rather than provider of this configuration
       file. </para></listitem>
     </itemizedlist>
 
-    <para>Note that the selected mode of operation for this file is detected fully automatically, depending on whether
+    <para>Note that the selected mode of operation for this file is detected fully automatically, depending
-    <filename>/etc/resolv.conf</filename> is a symlink to <filename>/run/systemd/resolve/resolv.conf</filename> or
+    on whether <filename>/etc/resolv.conf</filename> is a symlink to
-    lists 127.0.0.53 as DNS server.</para>
+    <filename>/run/systemd/resolve/resolv.conf</filename> or lists 127.0.0.53 as DNS server.</para>
   </refsect1>
 
   <refsect1>
@@ -235,20 +242,21 @@
         <term><constant>SIGUSR1</constant></term>
 
         <listitem><para>Upon reception of the <constant>SIGUSR1</constant> process signal
-        <command>systemd-resolved</command> will dump the contents of all DNS resource record caches it maintains, as
+        <command>systemd-resolved</command> will dump the contents of all DNS resource record caches it
-        well as all feature level information it learnt about configured DNS servers into the system
+        maintains, as well as all feature level information it learnt about configured DNS servers into the
-        logs.</para></listitem>
+        system logs.</para></listitem>
       </varlistentry>
 
       <varlistentry>
         <term><constant>SIGUSR2</constant></term>
 
         <listitem><para>Upon reception of the <constant>SIGUSR2</constant> process signal
-        <command>systemd-resolved</command> will flush all caches it maintains. Note that it should normally not be
+        <command>systemd-resolved</command> will flush all caches it maintains. Note that it should normally
-        necessary to request this explicitly – except for debugging purposes – as <command>systemd-resolved</command>
+        not be necessary to request this explicitly – except for debugging purposes – as
-        flushes the caches automatically anyway any time the host's network configuration changes. Sending this signal
+        <command>systemd-resolved</command> flushes the caches automatically anyway any time the host's
-        to <command>systemd-resolved</command> is equivalent to the <command>resolvectl flush-caches</command>
+        network configuration changes. Sending this signal to <command>systemd-resolved</command> is
-        command, however the latter is recommended since it operates in a synchronous way.</para></listitem>
+        equivalent to the <command>resolvectl flush-caches</command> command, however the latter is
+        recommended since it operates in a synchronous way.</para></listitem>
       </varlistentry>
 
       <varlistentry>
@@ -256,13 +264,14 @@
 
         <listitem><para>Upon reception of the <constant>SIGRTMIN+1</constant> process signal
         <command>systemd-resolved</command> will forget everything it learnt about the configured DNS
-        servers. Specifically any information about server feature support is flushed out, and the server feature
+        servers. Specifically any information about server feature support is flushed out, and the server
-        probing logic is restarted on the next request, starting with the most fully featured level. Note that it
+        feature probing logic is restarted on the next request, starting with the most fully featured
-        should normally not be necessary to request this explicitly – except for debugging purposes – as
+        level. Note that it should normally not be necessary to request this explicitly – except for
-        <command>systemd-resolved</command> automatically forgets learnt information any time the DNS server
+        debugging purposes – as <command>systemd-resolved</command> automatically forgets learnt information
-        configuration changes. Sending this signal to <command>systemd-resolved</command> is equivalent to the
+        any time the DNS server configuration changes. Sending this signal to
-        <command>resolvectl reset-server-features</command> command, however the latter is recommended since it
+        <command>systemd-resolved</command> is equivalent to the <command>resolvectl
-        operates in a synchronous way.</para></listitem>
+        reset-server-features</command> command, however the latter is recommended since it operates in a
+        synchronous way.</para></listitem>
       </varlistentry>
     </variablelist>
 

src/resolve/resolved-dns-scope.c

@@ -496,9 +496,8 @@ DnsScopeMatch dns_scope_good_domain(
         assert(s);
         assert(domain);
 
-        /* Checks if the specified domain is something to look up on
+        /* Checks if the specified domain is something to look up on this scope. Note that this accepts
-         * this scope. Note that this accepts non-qualified hostnames,
+         * non-qualified hostnames, i.e. those without any search path suffixed. */
-         * i.e. those without any search path prefixed yet. */
 
         if (ifindex != 0 && (!s->link || s->link->ifindex != ifindex))
                 return DNS_SCOPE_NO;