+ <sect id="bpp-debian-maint-scripts">
+ <heading>Best practices for maintainer scripts</heading>
+ <p>
+Maintainer scripts include the files <file>debian/postinst</file>,
+<file>debian/preinst</file>, <file>debian/prerm</file> and
+<file>debian/postrm</file>. These scripts take care of any package
+installation or deinstallation setup which isn't handled merely by the
+creation or removal of files and directories. The following
+instructions supplement the <url id="&url-debian-policy;" name="Debian
+Policy">.
+ <p>
+Maintainer scripts must be idempotent. That means that you need to
+make sure nothing bad will happen if the script is called twice where
+it would usually be called once.
+ <p>
+Standard input and output may be redirected (e.g. into pipes) for
+logging purposes, so don't rely on them being a tty.
+ <p>
+All prompting or interactive configuration should be kept to a
+minimum. When it is necessary, you should use the
+<package>debconf</package> package for the interface. Remember that
+prompting in any case can only be in the <tt>configure</tt> stage of
+the <file>postinst</file> script.
+ <p>
+Keep the maintainer scripts as simple as possible. We suggest you use
+pure POSIX shell scripts. Remember, if you do need any bash features,
+the maintainer script must have a bash sh-bang line. POSIX shell or
+Bash are preferred to Perl, since they enable
+<package>debhelper</package> to easily add bits to the scripts.
+ <p>
+If you change your maintainer scripts, be sure to test package
+removal, double installation, and purging. Be sure that a purged
+package is completely gone, that is, it must remove any files created,
+directly or indirectly, in any maintainer script.
+ <p>
+If you need to check for the existence of a command, you should use
+something like
+<example>if [ -x /usr/sbin/install-docs ]; then ...</example>
+
+If you don't wish to hard-code the path of the command in your
+maintainer script, the following POSIX-compliant shell function may
+help:
+
+&example-pathfind;
+
+You can use this function to search <tt>$PATH</tt> for a command name,
+passed as an argument. It returns true (zero) if the command was
+found, and false if not. This is really the most portable way, since
+<tt>command -v</tt>, <prgn>type</prgn>, and <prgn>which</prgn> are not
+POSIX. While <prgn>which</prgn> is an acceptable alternative, since
+it is from the required <package>debianutils</package> package, it's
+not on the root partition, although that is probably not something
+that will cause a problem.
+
+
+ <sect id="bpp-debian-control">
+ <heading>Best practices for <file>debian/control</file></heading>
+ <p>
+The following practices supplement the <url
+ id="&url-debian-policy;ch-miscellaneous.html#s-descriptions"
+ name="Policy on package descriptions">.</p>
+
+ <sect1 id="bpp-pkg-desc">
+ <heading>Writing useful descriptions</heading>
+ <p>
+The description of the package (as defined by the corresponding field
+in the <file>control</file> file) is the primary information available
+to the user about a package before they install it. It should provide
+all the required information to let the user decide whether to install
+the package.
+ <p>
+For consistency and aesthetics, you should capitalize the first letter
+of the Synopsis. Don't put a full stop (period) at the end. The
+description itself should consist of full sentences.
+ <p>
+Since the first user impression is based on the description, be
+careful to avoid spelling and grammar mistakes. Ensure that you
+spell-check it. <prgn>ispell</prgn> has a special <tt>-g</tt> option
+for <file>debian/control</file> files:
+
+<example>ispell -d american -g debian/control</example>
+
+If you want someone to proofread the description that you
+intend to use you may ask on &email-debian-l10n-english;.
+ </sect1>
+
+ <sect1 id="bpp-upstream-info">
+ <heading>Upstream home page</heading>
+ <p>
+We recommend that you add the URL for the package's home page to the
+package description in <file>debian/control</file>. This information
+should be added at the
+end of description, using the following format:
+
+<example> .
+ Homepage: http://some-project.some-place.org/</example>
+
+Note the spaces prepending the line, which serves to break the lines
+correctly. To see an example of how this displays, see <url
+id="&url-eg-desc-upstream-info;">.
+ <p>
+If there is no home page for the software, this should naturally be
+left empty.
+ <p>
+Note that we expect this field will eventually be replaced by a proper
+<file>debian/control</file> field understood by <prgn>dpkg</prgn> and
+<tt>&packages-host;</tt>. If you don't want to bother migrating the
+home page from the description to this field, you should probably wait
+until that is available.</p>
+ </sect1>
+ </sect>
+