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-              r2bf32ff
+              r4349661
   <para>Package Management is an often requested addition to the LFS Book. A
   Package Manager allows tracking the installation of files making it easy to
+  Package Manager tracks the installation of files, making it easier to
   remove and upgrade packages. As well as the binary and library files, a
   package manager will handle the installation of configuration files.  Before
 …
   any particular package manager. What it provides is a roundup of the more
   popular techniques and how they work. The perfect package manager for you may
   be among these techniques or may be a combination of two or more of these
+  be among these techniques, or it may be a combination of two or more of these
   techniques. This section briefly mentions issues that may arise when upgrading
   packages.</para>
 …
     <listitem>
       <para>There are multiple solutions for package management, each having
       its strengths and drawbacks.  Including one that satisfies all audiences
+      its strengths and drawbacks.  Finding one solution that satisfies all audiences
       is difficult.</para>
     </listitem>
 …
   <para>There are some hints written on the topic of package management. Visit
   the <ulink url="&hints-root;">Hints Project</ulink> and see if one of them
   fits your need.</para>
+  fits your needs.</para>
   <sect2 id='pkgmgmt-upgrade-issues'>
 …
     <itemizedlist>
       <listitem>
         <para>If Linux kernel needs to be upgraded (for example, from
 .10.17 to 5.10.18 or 5.11.1), nothing else need to be rebuilt.
         The system will keep working fine thanks to the well-defined border
         between kernel and userspace.  Specifically, Linux API headers
         need not to be (and should not be, see the next item) upgraded
         alongside the kernel.  You'll need to reboot your system to use the
+        <para>If the Linux kernel needs to be upgraded (for example, from
+.10.17 to 5.10.18 or 5.11.1), nothing else needs to be rebuilt.
+        The system will keep working fine thanks to the well-defined interface
+        between the kernel and user space.  Specifically, Linux API headers
+        need not be (and should not be, see the next item) upgraded
+        along with the kernel.  You will merely need to reboot your system to use the
         upgraded kernel.</para>
       </listitem>
       <listitem>
         <para>If Linux API headers or Glibc needs to be upgraded to a newer
         version, (e.g.  from glibc-2.31 to glibc-2.32), it is safer to
+        <para>If Linux API headers or glibc need to be upgraded to a newer
+        version, (e.g.,  from glibc-2.31 to glibc-2.32), it is safer to
         rebuild LFS.  Though you <emphasis>may</emphasis> be able to rebuild
         all the packages in their dependency order, we do not recommend
 …
       <listitem> <para>If a package containing a shared library is updated, and
       if the name of the library changes, then any packages dynamically
       linked to the library need to be recompiled in order to link against the
+      linked to the library must be recompiled, to link against the
       newer library.  (Note that there is no correlation between the package
       version and the name of the library.) For example, consider a package
       foo-1.2.3 that installs a shared library with name <filename
       class='libraryfile'>libfoo.so.1</filename>. If you upgrade the package to
       a newer version foo-1.2.4 that installs a shared library with name
+      foo-1.2.3 that installs a shared library with the name <filename
+      class='libraryfile'>libfoo.so.1</filename>. Suppose you upgrade the package to
+      a newer version foo-1.2.4 that installs a shared library with the name
       <filename class='libraryfile'>libfoo.so.2</filename>. In this case, any
       packages that are dynamically linked to <filename
       class='libraryfile'>libfoo.so.1</filename> need to be recompiled to link
       against <filename class='libraryfile'>libfoo.so.2</filename> in order to
       use the new library version. You should not remove the previous
       libraries unless all the dependent packages are recompiled.</para>
+      use the new library version. You should not remove the old
+      libraries until all the dependent packages have been recompiled.</para>
       </listitem>
       <listitem> <para>If a package containing a shared library is updated,
       and the name of library doesn't change, but the version number of the
+      and the name of the library doesn't change, but the version number of the
       library <emphasis role="bold">file</emphasis> decreases (for example,
       the name of the library is kept named
+      the library is still named
       <filename class='libraryfile'>libfoo.so.1</filename>,
       but the name of library file is changed from
+      but the name of the library file is changed from
       <filename class='libraryfile'>libfoo.so.1.25</filename> to
       <filename class='libraryfile'>libfoo.so.1.24</filename>),
       you should remove the library file from the previously installed version
       (<filename class='libraryfile'>libfoo.so.1.25</filename> in the case).
       Or, a <command>ldconfig</command> run (by yourself using a command
+      (<filename class='libraryfile'>libfoo.so.1.25</filename> in this case).
+      Otherwise, a <command>ldconfig</command> command (invokeed by yourself from the command
       line, or by the installation of some package) will reset the symlink
       <filename class='libraryfile'>libfoo.so.1</filename> to point to
       the old library file because it seems having a <quote>newer</quote>
       version, as its version number is larger.  This situation may happen if
       you have to downgrade a package, or the package changes the versioning
       scheme of library files suddenly.</para> </listitem>
+      the old library file because it seems to be a <quote>newer</quote>
+      version; its version number is larger.  This situation may arise if
+      you have to downgrade a package, or if the authors change the versioning
+      scheme for library files.</para> </listitem>
       <listitem><para>If a package containing a shared library is updated,
       and the name of library doesn't change, but a severe issue
+      and the name of the library doesn't change, but a severe issue
       (especially, a security vulnerability) is fixed, all running programs
       linked to the shared library should be restarted.  The following
       command, run as <systemitem class="username">root</systemitem> after
       updating, will list what is using the old versions of those libraries
+      the update is cmplete, will list which processes are using the old versions of those libraries
       (replace <replaceable>libfoo</replaceable> with the name of the
       library):</para>
 …
       <para>
         If <application>OpenSSH</application> is being used for accessing
         the system and it is linked to the updated library, you need to
         restart <command>sshd</command> service, then logout, login again,
         and rerun that command to confirm nothing is still using the
+        If <application>OpenSSH</application> is being used to access
+        the system and it is linked to the updated library, you must
+        restart the <command>sshd</command> service, then logout, login again,
+        and rerun the preceding ps command to confirm that nothing is still using the
         deleted libraries.
       </para>
 …
       <para revision='systemd'>
         If the <command>systemd</command> daemon (running as PID 1) is
         linked to the updated library, you can restart it without reboot
+        linked to the updated library, you can restart it without rebooting
         by running <command>systemctl daemon-reexec</command> as the
         <systemitem class='username'>root</systemitem> user.
 …
       <listitem>
         <para>If a binary or a shared library is overwritten, the processes
         using the code or data in the binary or library may crash.  The
         correct way to update a binary or a shared library without causing
+        <para>If an executable program or a shared library is overwritten, the processes
+        using the code or data in that program or library may crash.  The
+        correct way to update a program or a shared library without causing
         the process to crash is to remove it first, then install the new
         version into position. The <command>install</command> command
         provided by <application>Coreutils</application> has already
         implemented this and most packages use it to install binaries and
+        version. The <command>install</command> command
+        provided by <application>coreutils</application> has already
+        implemented this, and most packages use that command to install binary files and
         libraries.  This means that you won't be troubled by this issue most of the time.
         However, the install process of some packages (notably Mozilla JS
         in BLFS) just overwrites the file if it exists and causes a crash, so
+        in BLFS) just overwrites the file if it exists; this causes a crash. So
         it's safer to save your work and close unneeded running processes
         before updating a package.</para>
+        before updating a package.</para> <!-- binary is an adjective, not a noun. -->
       </listitem>
     </itemizedlist>
 …
     <para>The following are some common package management techniques. Before
     making a decision on a package manager, do some research on the various
     techniques, particularly the drawbacks of the particular scheme.</para>
+    techniques, particularly the drawbacks of each particular scheme.</para>
     <sect3>
       <title>It is All in My Head!</title>
       <para>Yes, this is a package management technique. Some folks do not find
       the need for a package manager because they know the packages intimately
       and know what files are installed by each package. Some users also do not
+      <para>Yes, this is a package management technique. Some folks do not
+      need a package manager because they know the packages intimately
+      and know which files are installed by each package. Some users also do not
       need any package management because they plan on rebuilding the entire
       system when a package is changed.</para>
+      system whenever a package is changed.</para>
     </sect3>
 …
       <title>Install in Separate Directories</title>
       <para>This is a simplistic package management that does not need any extra
       package to manage the installations. Each package is installed in a
+      <para>This is a simplistic package management technique that does not need a
+      special program to manage the packages. Each package is installed in a
       separate directory. For example, package foo-1.1 is installed in
       <filename class='directory'>/usr/pkg/foo-1.1</filename>
       and a symlink is made from <filename>/usr/pkg/foo</filename> to
       <filename class='directory'>/usr/pkg/foo-1.1</filename>. When installing
       a new version foo-1.2, it is installed in
+      <filename class='directory'>/usr/pkg/foo-1.1</filename>. When
+      a new version foo-1.2 comes along, it is installed in
       <filename class='directory'>/usr/pkg/foo-1.2</filename> and the previous
       symlink is replaced by a symlink to the new version.</para>
 …
       <envar>LD_LIBRARY_PATH</envar>, <envar>MANPATH</envar>,
       <envar>INFOPATH</envar> and <envar>CPPFLAGS</envar> need to be expanded to
       include <filename>/usr/pkg/foo</filename>. For more than a few packages,
+      include <filename>/usr/pkg/foo</filename>. If you install more than a few packages,
       this scheme becomes unmanageable.</para>
 …
       <para>This is a variation of the previous package management technique.
       Each package is installed similar to the previous scheme. But instead of
       making the symlink, each file is symlinked into the
+      Each package is installed as in the previous scheme. But instead of
+      making the symlink via a generic package name, each file is symlinked into the
       <filename class='directory'>/usr</filename> hierarchy. This removes the
       need to expand the environment variables. Though the symlinks can be
       created by the user to automate the creation, many package managers have
       been written using this approach. A few of the popular ones include Stow,
+      created by the user, many package managers use this approach, and
+      automate the creation of the symlinks. A few of the popular ones include Stow,
       Epkg, Graft, and Depot.</para>
       <para>The installation needs to be faked, so that the package thinks that
+      <para>The installation script needs to be fooled, so the package thinks
       it is installed in <filename class="directory">/usr</filename> though in
       reality it is installed in the
 …
       instead of <filename class='libraryfile'>/usr/lib/libfoo.so.1</filename>
       as you would expect. The correct approach is to use the
       <envar>DESTDIR</envar> strategy to fake installation of the package. This
+      <envar>DESTDIR</envar> variable to direct the installation. This
       approach works as follows:</para>
 …
       <para>Most packages support this approach, but there are some which do not.
       For the non-compliant packages, you may either need to manually install the
       package, or you may find that it is easier to install some problematic
+      For the non-compliant packages, you may either need to install the
+      package manually, or you may find that it is easier to install some problematic
       packages into <filename class='directory'>/opt</filename>.</para>
 …
       <command>find</command> command with the appropriate options can generate
       a log of all the files installed after the timestamp file was created. A
       package manager written with this approach is install-log.</para>
+      package manager that uses this approach is install-log.</para>
       <para>Though this scheme has the advantage of being simple, it has two
       drawbacks. If, during installation, the files are installed with any
       timestamp other than the current time, those files will not be tracked by
       the package manager. Also, this scheme can only be used when one package
       is installed at a time. The logs are not reliable if two packages are
       being installed on two different consoles.</para>
+      the package manager. Also, this scheme can only be used when packages
+      are installed one at a time. The logs are not reliable if two packages are
+      installed simultaneously from two different consoles.</para>
     </sect3>
 …
       executables need to be dynamically linked without the suid or sgid bit.
       Preloading the library may cause some unwanted side-effects during
       installation. Therefore, it is advised that one performs some tests to
       ensure that the package manager does not break anything and logs all the
+      installation. Therefore, it's a good idea to perform some tests to
+      ensure that the package manager does not break anything, and that it logs all the
       appropriate files.</para>
       <para>The second technique is to use <command>strace</command>, which
       logs all system calls made during the execution of the installation
+      <para>Another technique is to use <command>strace</command>, which
+      logs all the system calls made during the execution of the installation
       scripts.</para>
     </sect3>
 …
       <para>In this scheme, the package installation is faked into a separate
       tree as described in the Symlink style package management. After the
+      tree as previously described in the symlink style package management section. After the
       installation, a package archive is created using the installed files.
       This archive is then used to install the package either on the local
       machine or can even be used to install the package on other machines.</para>
+      This archive is then used to install the package on the local
+      machine or even on other machines.</para>
       <para>This approach is used by most of the package managers found in the
 …
       url="&hints-root;fakeroot.txt"/>.</para>
       <para>Creation of package files that include dependency information is
       complex and is beyond the scope of LFS.</para>
       <para>Slackware uses a <command>tar</command> based system for package
+      <para>The creation of package files that include dependency information is
+      complex, and beyond the scope of LFS.</para>
+      <para>Slackware uses a <command>tar</command>-based system for package
       archives.  This system purposely does not handle package dependencies
       as more complex package managers do.  For details of Slackware package
 …
     simple as using <command>tar</command> on the LFS partition that contains
     the root directory (about 250MB uncompressed for a base LFS build), copying
     that file via network transfer or CD-ROM to the new system and expanding
     it.  From that point, a few configuration files will have to be changed.
+    that file via network transfer or CD-ROM / USB stick to the new system, and expanding
+    it.  After that, a few configuration files will have to be changed.
     Configuration files that may need to be updated include:
     <filename>/etc/hosts</filename>,
 …
     </para>
     <para>A custom kernel may need to be built for the new system depending on
+    <para>A custom kernel may be needed for the new system, depending on
     differences in system hardware and the original kernel
     configuration.</para>
 …
     <note><para>There have been some reports of issues when copying between
     similar but not identical architectures. For instance, the instruction set
     for an Intel system is not identical with an AMD processor and later
     versions of some processors may have instructions that are unavailable in
+    for an Intel system is not identical with the AMD processor's instructions, and later
+    versions of some processors may provide instructions that are unavailable with
     earlier versions.</para></note>
     <para>Finally the new system has to be made bootable via <xref
+    <para>Finally, the new system has to be made bootable via <xref
     linkend="ch-bootable-grub"/>.</para>

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