From 6e11fe27286d9202280771ad1a402657e67ee065 Mon Sep 17 00:00:00 2001
From: Xi Ruoyao <xry111@xry111.site>
Date: Sat, 30 Sep 2023 16:11:57 +0800
Subject: [PATCH 1/2] createfiles: Add Y2038 info about the traditional
 {b,u,w}tmp and lastlog files

And utmp does not exist on systemd-based LFS.
---
 chapter07/createfiles.xml | 21 ++++++++++++++++++---
 1 file changed, 18 insertions(+), 3 deletions(-)

diff --git a/chapter07/createfiles.xml b/chapter07/createfiles.xml
index 2b752b944..ec4b0eee2 100644
--- a/chapter07/createfiles.xml
+++ b/chapter07/createfiles.xml
@@ -215,8 +215,23 @@ chmod -v 600  /var/log/btmp</userinput></screen>
   failed login attempts.  The <filename>/var/log/btmp</filename> file records
   the bad login attempts.</para>
 
-  <note><para>The <filename>/run/utmp</filename> file records the users that
-  are currently logged in.  This file is created dynamically in the boot
-  scripts.</para></note>
+  <!-- systemd no longer creates this -->
+  <note revision='sysv'><para>The <filename>/run/utmp</filename> file
+  records the users that are currently logged in.  This file is created
+  dynamically in the boot scripts.</para></note>
+
+  <!-- AFAIK they are not vital for system function, users requiring such
+       info should rely on systemd-logind or elogind or some custom PAM
+       module.  Maybe we can stop to create them at all.  -->
+  <note>
+    <para>
+      The <phrase revision='sysv'><filename>utmp</filename>,
+      </phrase><filename>wtmp</filename>, <filename>btmp</filename>, and
+      <filename>lastlog</filename> files use 32-bit integers for timestamp
+      and they'll be fundamentally broken after year 2038.  Many packages
+      have stopped using them and other packages are going to stop using
+      them.  Do not rely on the contents of them for anything.
+    </para>
+  </note>
 
 </sect1>

From c7cd2c71e7f96bcc42f91399098f083beb757788 Mon Sep 17 00:00:00 2001
From: Xi Ruoyao <xry111@xry111.site>
Date: Sat, 30 Sep 2023 16:14:17 +0800
Subject: [PATCH 2/2] shadow: Remove lastlog from contents

It's deprecated because of Y2038 issue and no longer being built by
default.
---
 chapter08/shadow.xml | 13 +------------
 1 file changed, 1 insertion(+), 12 deletions(-)

diff --git a/chapter08/shadow.xml b/chapter08/shadow.xml
index f88216a5b..315234c7f 100644
--- a/chapter08/shadow.xml
+++ b/chapter08/shadow.xml
@@ -276,7 +276,7 @@ useradd -D --gid 999</userinput></screen>
       <seglistitem>
         <seg>chage, chfn, chgpasswd, chpasswd, chsh, expiry, faillog,
         getsubids, gpasswd, groupadd, groupdel, groupmems, groupmod, grpck,
-        grpconv, grpunconv, lastlog, login, logoutd, newgidmap, newgrp,
+        grpconv, grpunconv, login, logoutd, newgidmap, newgrp,
         newuidmap, newusers, nologin, passwd, pwck, pwconv, pwunconv,
         sg (link to newgrp), su, useradd, userdel, usermod,
         vigr (link to vipw), and vipw</seg>
@@ -459,17 +459,6 @@ useradd -D --gid 999</userinput></screen>
         </listitem>
       </varlistentry>
 
-      <varlistentry id="lastlog">
-        <term><command>lastlog</command></term>
-        <listitem>
-          <para>Reports the most recent login of all users or of a
-          given user</para>
-          <indexterm zone="ch-system-shadow lastlog">
-            <primary sortas="b-lastlog">lastlog</primary>
-          </indexterm>
-        </listitem>
-      </varlistentry>
-
       <varlistentry id="login">
         <term><command>login</command></term>
         <listitem>