support setting empty values (sanely) & removing support for

[apt.git] / doc / apt-cache.8.xml

diff --git a/doc/apt-cache.8.xml b/doc/apt-cache.8.xml
index ac3aaa37a827d66dc3a2c205f94c3efb62b653e0..a76eb1000db8eeb88df7eca6255d052debb14d85 100644 (file)
--- a/doc/apt-cache.8.xml
+++ b/doc/apt-cache.8.xml
@@ -32,10 +32,16 @@
  &synopsis-command-apt-cache;
 
  <refsect1><title>Description</title>
-   <para><command>apt-cache</command> performs a variety of operations on APT's package 
-   cache. <command>apt-cache</command> does not manipulate the state of the system 
-   but does provide operations to search and generate interesting output 
-   from the package metadata.</para>
+    <para>
+       <command>apt-cache</command> performs a variety of operations on APT's
+       package cache. <command>apt-cache</command> does not manipulate the
+       state of the system but does provide operations to search and generate
+       interesting output from the package metadata. The metadata is acquired
+       and updated via the 'update' command of e.g. <command>apt-get</command>,
+       so that it can be outdated if the last update is too long ago, but in
+       exchange <command>apt-cache</command> works independently of the
+       availability of the configured sources (e.g. offline).
+    </para>
 
    <para>Unless the <option>-h</option>, or <option>--help</option> option is given, one of the
    commands below must be present.</para>
@@ -122,8 +128,7 @@ Reverse Provides:
        </listitem>
 
        <listitem><para><literal>Total distinct</literal> versions is the number of package versions 
-       found in the cache; this value is therefore at least equal to the 
-       number of total package names. If more than one distribution is being accessed
+       found in the cache. If more than one distribution is being accessed
        (for instance, "stable" and "unstable"), this value
        can be considerably larger than the number of total package names.</para>
        </listitem>
@@ -136,9 +141,12 @@ Reverse Provides:
      </varlistentry>
      
      <varlistentry><term><option>showsrc</option> <option><replaceable>&synopsis-pkg;</replaceable>…</option></term>
-     <listitem><para><literal>showsrc</literal> displays all the source package records that match
-     the given package names. All versions are shown, as well as all 
-     records that declare the name to be a binary package.</para></listitem>
+     <listitem><para><literal>showsrc</literal> displays all the
+     source package records that match the given package names. All
+     versions are shown, as well as all records that declare the name
+     to be a binary package. Use <option>--only-source</option> to
+     display only source package names.
+     </para></listitem>
      </varlistentry>
      
      <varlistentry><term><option>dump</option></term>