[developers-reference.git] / pkgs.dbk

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<chapter id="pkgs">
<title>Managing Packages</title>
<para>
This chapter contains information related to creating, uploading, maintaining,
and porting packages.
</para>
<section id="newpackage">
<title>New packages</title>
<para>
If you want to create a new package for the Debian distribution, you should
first check the <ulink url="&url-wnpp;">Work-Needing and
Prospective Packages (WNPP)</ulink> list.  Checking the WNPP list ensures that
no one is already working on packaging that software, and that effort is not
duplicated.  Read the <ulink url="&url-wnpp;">WNPP web
pages</ulink> for more information.
</para>
<para>
Assuming no one else is already working on your prospective package, you must
then submit a bug report (<xref linkend="submit-bug"/>) against the
pseudo-package <systemitem role="package">wnpp</systemitem> describing your
plan to create a new package, including, but not limiting yourself to, the
description of the package (so that others can review it),
the license of the prospective package, and the
current URL where it can be downloaded from.
</para>
<para>
You should set the subject of the bug to <literal>ITP:
<replaceable>foo</replaceable> -- <replaceable>short
description</replaceable></literal>, substituting the name of the new
package for <replaceable>foo</replaceable>.
The severity of the bug report must be set to <literal>wishlist</literal>.
Please send a copy to &email-debian-devel; by using the X-Debbugs-CC
header (don't use CC:, because that way the message's subject won't
indicate the bug number). If you are packaging so many new packages (>10)
that notifying the mailing list in separate messages is too disruptive,
send a summary after filing the bugs to the debian-devel list instead.
This will inform the other developers about upcoming packages and will
allow a review of your description and package name.
</para>
<para>
Please include a <literal>Closes: #<replaceable>nnnnn</replaceable></literal>
entry in the changelog of the new package in order for the bug report to
be automatically closed once the new package is installed in the archive
(see <xref linkend="upload-bugfix"/>).
</para>
<para>
If you think your package needs some explanations for the administrators of the
NEW package queue, include them in your changelog, send to &email-ftpmaster;
a reply to the email you receive as a maintainer after your upload, or reply to
the rejection email in case you are already re-uploading.
</para>
<para>
When closing security bugs include CVE numbers as well as the
<literal>Closes: #<replaceable>nnnnn</replaceable></literal>.  
This is useful for the security team to track vulnerabilities.  If an upload is
made to fix the bug before the advisory ID is known, it is encouraged to modify
the historical changelog entry with the next upload.  Even in this case, please
include all available pointers to background information in the original
changelog entry.
</para>
<para>
There are a number of reasons why we ask maintainers to announce their
intentions:
</para>
<itemizedlist>
<listitem>
<para>
It helps the (potentially new) maintainer to tap into the experience of people
on the list, and lets them know if anyone else is working on it already.
</para>
</listitem>
<listitem>
<para>
It lets other people thinking about working on the package know that there
already is a volunteer, so efforts may be shared.
</para>
</listitem>
<listitem>
<para>
It lets the rest of the maintainers know more about the package than the one
line description and the usual changelog entry ``Initial release'' that gets
posted to &email-debian-devel-changes;.
</para>
</listitem>
<listitem>
<para>
It is helpful to the people who live off <literal>unstable</literal> (and form
our first line of testers).  We should encourage these people.
</para>
</listitem>
<listitem>
<para>
The announcements give maintainers and other interested parties a better feel
of what is going on, and what is new, in the project.
</para>
</listitem>
</itemizedlist>
<para>
Please see <ulink url="https://&ftp-master-host;/REJECT-FAQ.html"></ulink>
for common rejection reasons for a new package.
</para>
</section>

<section id="changelog-entries">
<title>Recording changes in the package</title>
<para>
Changes that you make to the package need to be recorded in the
<filename>debian/changelog</filename>.  These changes should provide a concise
description of what was changed, why (if it's in doubt), and note if any bugs
were closed.  They also record when the package was completed.  This file will
be installed in
<filename>/usr/share/doc/<replaceable>package</replaceable>/changelog.Debian.gz</filename>,
or
<filename>/usr/share/doc/<replaceable>package</replaceable>/changelog.gz</filename>
for native packages.
</para>
<para>
The <filename>debian/changelog</filename> file conforms to a certain structure,
with a number of different fields.  One field of note, the
<literal>distribution</literal>, is described in <xref
linkend="distribution"/>.  More information about the structure of this file
can be found in the Debian Policy section titled
<filename>debian/changelog</filename>.
</para>
<para>
Changelog entries can be used to automatically close Debian bugs when the
package is installed into the archive.  See <xref linkend="upload-bugfix"/>.
</para>
<para>
It is conventional that the changelog entry of a package that contains a new
upstream version of the software looks like this:
</para>
<screen>
  * New upstream release.
</screen>
<para>
There are tools to help you create entries and finalize the
<filename>changelog</filename> for release — see <xref linkend="devscripts"/>
and <xref linkend="dpkg-dev-el"/>.
</para>
<para>
See also <xref linkend="bpp-debian-changelog"/>.
</para>
</section>

<section id="sanitycheck">
<title>Testing the package</title>
<para>
Before you upload your package, you should do basic testing on it.  At a
minimum, you should try the following activities (you'll need to have an older
version of the same Debian package around):
</para>
<itemizedlist>
<listitem>
<para>
Install the package and make sure the software works, or upgrade the package
from an older version to your new version if a Debian package for it already
exists.
</para>
</listitem>
<listitem>
<para>
Run <command>lintian</command> over the package.  You can run
<command>lintian</command> as follows: <literal>lintian -v
<replaceable>package-version</replaceable>.changes</literal>.  This will check
the source package as well as the binary package.  If you don't understand the
output that <command>lintian</command> generates, try adding the
<literal>-i</literal> switch, which will cause <command>lintian</command> to
output a very verbose description of the problem.
</para>
<para>
Normally, a package should <emphasis>not</emphasis> be uploaded if it causes
<command>lintian</command> to emit errors (they will start with <literal>E</literal>).
</para>
<para>
For more information on <command>lintian</command>, see <xref
linkend="lintian"/>.
</para>
</listitem>
<listitem>
<para>
Optionally run <command>debdiff</command> (see <xref linkend="debdiff"/>) to analyze changes from an older
version, if one exists.
</para>
</listitem>
<listitem>
<para>
Downgrade the package to the previous version (if one exists) — this tests
the <filename>postrm</filename> and <filename>prerm</filename> scripts.
</para>
</listitem>
<listitem>
<para>
Remove the package, then reinstall it.
</para>
</listitem>
<listitem>
<para>
Copy the source package in a different directory and try unpacking it and
rebuilding it.  This tests if the package relies on existing files outside of
it, or if it relies on permissions being preserved on the files shipped inside
the <filename>.diff.gz</filename> file.
</para>
</listitem>
</itemizedlist>
</section>

<section id="sourcelayout">
<title>Layout of the source package</title>
<para>
There are two types of Debian source packages:
</para>
<itemizedlist>
<listitem>
<para>
the so-called <literal>native</literal> packages, where there is no
distinction between the original sources and the patches applied for Debian
</para>
</listitem>
<listitem>
<para>
the (more common) packages where there's an original source tarball file
accompanied by another file that contains the changes made by Debian
</para>
</listitem>
</itemizedlist>
<para>
For the native packages, the source package includes a Debian source control
file (<filename>.dsc</filename>) and the source tarball
(<filename>.tar.{gz,bz2,xz}</filename>). A source package of a non-native package
includes a Debian source control file, the original source tarball
(<filename>.orig.tar.{gz,bz2,xz}</filename>) and the Debian changes
(<filename>.diff.gz</filename> for the source format “1.0” or
<filename>.debian.tar.{gz,bz2,xz}</filename> for the source format “3.0 (quilt)”).
</para>
<para>
With source format “1.0”, whether a package is native or not was determined
by <command>dpkg-source</command> at build time. Nowadays it is recommended
to be explicit about the desired source format by putting either “3.0 (quilt)”
or “3.0 (native)” in <filename>debian/source/format</filename>.
The rest of this section relates only to non-native packages.
</para>
<para>
The first time a version is uploaded which corresponds to a particular upstream
version, the original source tar file should be uploaded and included in the
<filename>.changes</filename> file.  Subsequently, this very same tar file
should be used to build the new diffs and <filename>.dsc</filename> files, and
will not need to be re-uploaded.
</para>
<para>
By default, <command>dpkg-genchanges</command> and
<command>dpkg-buildpackage</command> will include the original source tar file
if and only if the current changelog entry has a different upstream version
from the preceding entry. This behavior may be modified by using
<literal>-sa</literal> to always include it or <literal>-sd</literal> to always
leave it out.
</para>
<para>
If no original source is included in the upload, the original source tar-file
used by <command>dpkg-source</command> when constructing the
<filename>.dsc</filename> file and diff to be uploaded
<emphasis>must</emphasis> be byte-for-byte identical with the one already in
the archive.
</para>
<para>
Please notice that, in non-native packages, permissions on files that are not
present in the <filename>*.orig.tar.{gz,bz2,xz}</filename> will not be preserved, as diff does not store file
permissions in the patch. However when using source format “3.0 (quilt)”,
permissions of files inside the <filename>debian</filename> directory are
preserved since they are stored in a tar archive.
</para>
</section>

<section id="distribution">
<title>Picking a distribution</title>
<para>
Each upload needs to specify which distribution the package is intended for.
The package build process extracts this information from the first line of the
<filename>debian/changelog</filename> file and places it in the
<literal>Distribution</literal> field of the <filename>.changes</filename> file.
</para>
<para>
There are several possible values for this field: <literal>stable</literal>,
<literal>unstable</literal>, <literal>testing-proposed-updates</literal> and
<literal>experimental</literal>.  Normally, packages are uploaded into
<literal>unstable</literal>.
</para>
<para>
Actually, there are other possible distributions:
<replaceable>codename</replaceable><literal>-security</literal>,
but read <xref linkend="bug-security"/> for more information on those.
</para>
<para>
It is not possible to upload a package into several distributions at the same
time.
</para>
<section id="upload-stable">
<title>Special case: uploads to the <literal>stable</literal> and
<literal>oldstable</literal> distributions</title>
<para>
Uploading to <literal>stable</literal> means that the package will transferred
to the <literal>proposed-updates-new</literal> queue for review by the stable
release managers, and if approved will be installed in
<filename>stable-proposed-updates</filename> directory of the Debian archive.
From there, it will be included in <literal>stable</literal> with the next
point release.
</para>
<para>
To ensure that your upload will be accepted, you should discuss the changes
with the stable release team before you upload. For that, file a bug against
the <systemitem role="package">release.debian.org</systemitem> pseudo-package
using <command>reportbug</command>, including the patch you want to
apply to the package version currently in <literal>stable</literal>. Always
be verbose and detailed in your changelog entries for uploads to the
<literal>stable</literal> distribution.
</para>
<para>
Extra care should be taken when uploading to <literal>stable</literal>.
Basically, a package should only be uploaded to <literal>stable</literal> if
one of the following happens:
</para>
<itemizedlist>
<listitem>
<para>
a truly critical functionality problem
</para>
</listitem>
<listitem>
<para>
the package becomes uninstallable
</para>
</listitem>
<listitem>
<para>
a released architecture lacks the package
</para>
</listitem>
</itemizedlist>
<para>
In the past, uploads to <literal>stable</literal> were used to address
security problems as well.  However, this practice is deprecated, as uploads
used for Debian security advisories are automatically copied to the appropriate
<filename>proposed-updates</filename> archive when the advisory is released.
See <xref linkend="bug-security"/> for detailed information on handling
security problems. If the security teams deems the problem to be too
benign to be fixed through a <literal>DSA</literal>, the stable release
managers are usually willing to include your fix nonetheless in a regular
upload to <literal>stable</literal>.
</para>
<para>
Changing anything else in the package that isn't important is discouraged,
because even trivial fixes can cause bugs later on.
</para>
<para>
Packages uploaded to <literal>stable</literal> need to be compiled on systems
running <literal>stable</literal>, so that their dependencies are limited to
the libraries (and other packages) available in <literal>stable</literal>;
for example, a package uploaded to <literal>stable</literal> that depends on
a library package that only exists in <literal>unstable</literal> will be
rejected.  Making changes to dependencies of other packages (by messing with
<literal>Provides</literal> or <filename>shlibs</filename> files), possibly
making those other packages uninstallable, is strongly discouraged.
</para>
<para>
Uploads to the <literal>oldstable</literal> distributions are possible as
long as it hasn't been archived. The same rules as for <literal>stable</literal>
apply.
</para>
</section>

<section id="upload-t-p-u">
<title>Special case: uploads to <literal>testing/testing-proposed-updates</literal></title>
<para>
Please see the information in the <link linkend="t-p-u">testing
section</link> for details.
</para>
</section>

</section>

<section id="upload">
<title>Uploading a package</title>
<section id="upload-ftp-master">
<title>Uploading to <literal>ftp-master</literal></title>
<para>
To upload a package, you should upload the files (including the signed changes
and dsc-file) with anonymous ftp to <literal>&ftp-upload-host;</literal> in
the directory <ulink
url="ftp://&ftp-upload-host;&upload-queue;">&upload-queue;</ulink>.
To get the files processed there, they need to be signed with a key in the
Debian Developers keyring or the Debian Maintainers keyring
(see <ulink url="&url-wiki-dm;"></ulink>).
</para>
<para>
Please note that you should transfer the changes file last.  Otherwise, your
upload may be rejected because the archive maintenance software will parse the
changes file and see that not all files have been uploaded.
</para>
<para>
You may also find the Debian packages <link linkend="dupload">dupload</link>
or <link linkend="dput">dput</link> useful when uploading packages.These
handy programs help automate the process of uploading packages into Debian.
</para>
<para>
For removing packages, please see
<ulink url="ftp://&ftp-upload-host;&upload-queue;README"/> and
the Debian package <link linkend="dcut">dcut</link>.
</para>
</section>

<section id="delayed-incoming">
<title>Delayed uploads</title>

<para>
It is sometimes useful to upload a package immediately, but to want this
package to arrive in the archive only a few days later. For example,
when preparing a <link linkend="nmu">Non-Maintainer Upload</link>,
you might want to give the maintainer a few days to react.
</para>

<para>
An upload to the delayed directory keeps the package in
<ulink url="https://ftp-master.debian.org/deferred.html">the deferred uploads queue</ulink>.
When the specified waiting time is over, the package is moved into
the regular incoming directory for processing.
This is done through automatic uploading to
<literal>&ftp-upload-host;</literal> in upload-directory
<literal>DELAYED/<replaceable>X</replaceable>-day</literal>
(<replaceable>X</replaceable> between 0 and 15). 0-day is uploaded
multiple times per day to <literal>&ftp-upload-host;</literal>.
</para>
<para>
With dput, you can use the <literal>--delayed <replaceable>DELAY</replaceable></literal>
parameter to put the package into one of the queues.
</para>
</section>

<section id="s5.6.4">
<title>Security uploads</title>
<para>
Do <emphasis role="strong">NOT</emphasis> upload a package to the security
upload queue (on <literal>security-master.debian.org</literal>)
without prior authorization from the security team.  If the
package does not exactly meet the team's requirements, it will cause many
problems and delays in dealing with the unwanted upload.  For details, please
see <xref linkend="bug-security"/>.
</para>
</section>

<section id="s5.6.5">
<title>Other upload queues</title>
<para>
There is an alternative upload queue in Europe at <ulink
url="ftp://&ftp-eu-upload-host;&upload-queue;"/>. It operates in
the same way as <literal>&ftp-upload-host;</literal>, but should be faster
for European developers.
</para>
<para>
Packages can also be uploaded via ssh to
<literal>&ssh-upload-host;</literal>; files should be put
<literal>/srv/upload.debian.org/UploadQueue</literal>. This queue does
not support <link linkend="delayed-incoming">delayed uploads</link>.
</para>
</section>

<section id="upload-notification">
<title>Notification that a new package has been installed</title>
<para>
The Debian archive maintainers are responsible for handling package uploads.
For the most part, uploads are automatically handled on a daily basis by the
archive maintenance tools, <command>dak process-upload</command>. Specifically,
updates to existing packages to the <literal>unstable</literal> distribution are
handled automatically. In other cases, notably new packages, placing the
uploaded package into the distribution is handled manually. When uploads are
handled manually, the change to the archive may take some time to occur. Please
be patient.
</para>
<para>
In any case, you will receive an email notification indicating that the package
has been added to the archive, which also indicates which bugs will be closed
by the upload.  Please examine this notification carefully, checking if any
bugs you meant to close didn't get triggered.
</para>
<para>
The installation notification also includes information on what section the
package was inserted into.  If there is a disparity, you will receive a
separate email notifying you of that.  Read on below.
</para>
<para>
Note that if you upload via queues, the queue daemon software will also send
you a notification by email.
</para>
</section>

</section>

<section id="override-file">
<title>Specifying the package section, subsection and priority</title>
<para>
The <filename>debian/control</filename> file's <literal>Section</literal> and
<literal>Priority</literal> fields do not actually specify where the file will
be placed in the archive, nor its priority.  In order to retain the overall
integrity of the archive, it is the archive maintainers who have control over
these fields.  The values in the <filename>debian/control</filename> file are
actually just hints.
</para>
<para>
The archive maintainers keep track of the canonical sections and priorities for
packages in the <literal>override file</literal>.  If there is a disparity
between the <literal>override file</literal> and the package's fields as
indicated in <filename>debian/control</filename>, then you will receive an
email noting the divergence when the package is installed into the archive.
You can either correct your <filename>debian/control</filename> file for your
next upload, or else you may wish to make a change in the <literal>override
file</literal>.
</para>
<para>
To alter the actual section that a package is put in, you need to first make
sure that the <filename>debian/control</filename> file in your package is
accurate.  Next, submit a
bug against <systemitem role="package">ftp.debian.org</systemitem> requesting
that the section or priority for your package be changed from the old section
or priority to the new one. Use a Subject like
<literal>override: PACKAGE1:section/priority, [...],
  PACKAGEX:section/priority</literal>, and include the justification for the
change in the body of the bug report.
</para>
<para>
For more information about <literal>override files</literal>, see
<citerefentry> <refentrytitle>dpkg-scanpackages</refentrytitle>
<manvolnum>1</manvolnum> </citerefentry> and <ulink
url="&url-bts-devel;#maintincorrect"></ulink>.
</para>
<para>
Note that the <literal>Section</literal> field describes both the section as
well as the subsection, which are described in <xref
linkend="archive-sections"/>.  If the section is main, it should be omitted.
The list of allowable subsections can be found in <ulink
url="&url-debian-policy;ch-archive.html#s-subsections"></ulink>.
</para>
</section>

<section id="bug-handling">
<title>Handling bugs</title>
<para>
Every developer has to be able to work with the Debian <ulink
url="&url-bts;">bug tracking system</ulink>.  This includes
knowing how to file bug reports properly (see <xref linkend="submit-bug"/>),
how to update them and reorder them, and how to process and close them.
</para>
<para>
The bug tracking system's features are described in the <ulink
url="&url-bts-devel;">BTS documentation for
developers</ulink>.  This includes closing bugs, sending followup messages,
assigning severities and tags, marking bugs as forwarded, and other issues.
</para>
<para>
Operations such as reassigning bugs to other packages, merging separate bug
reports about the same issue, or reopening bugs when they are prematurely
closed, are handled using the so-called control mail server.  All of the
commands available on this server are described in the <ulink
url="&url-bts-control;">BTS control server
documentation</ulink>.
</para>
<section id="bug-monitoring">
<title>Monitoring bugs</title>
<para>
If you want to be a good maintainer, you should periodically check the <ulink
url="&url-bts;">Debian bug tracking system (BTS)</ulink> for
your packages.  The BTS contains all the open bugs against your packages.  You
can check them by browsing this page:
<literal>https://&bugs-host;/<replaceable>yourlogin</replaceable>@debian.org</literal>.
</para>
<para>
Maintainers interact with the BTS via email addresses at
<literal>&bugs-host;</literal>.  Documentation on available
commands can be found at <ulink url="&url-bts;"></ulink>, or,
if you have installed the <systemitem role="package">doc-debian</systemitem>
package, you can look at the local files &file-bts-docs;.
</para>
<para>
Some find it useful to get periodic reports on open bugs.  You can add a cron
job such as the following if you want to get a weekly email outlining all the
open bugs against your packages:
</para>
<screen>
# ask for weekly reports of bugs in my packages
&cron-bug-report;
</screen>
<para>
Replace <replaceable>address</replaceable> with your official Debian maintainer
address.
</para>
</section>

<section id="bug-answering">
<title>Responding to bugs</title>
<para>
When responding to bugs, make sure that any discussion you have about bugs is
sent both to the original submitter of the bug, and to the bug itself (e.g.,
<email><replaceable>123</replaceable>@&bugs-host;</email>).  If you're writing a new mail and you
don't remember the submitter email address, you can use the
<email><replaceable>123</replaceable>-submitter@&bugs-host;</email> email to contact the submitter
<emphasis>and</emphasis> to record your mail within the bug log (that means you
don't need to send a copy of the mail to <email><replaceable>123</replaceable>@&bugs-host;</email>).
</para>
<para>
If you get a bug which mentions FTBFS, this means Fails to build from source.
Porters frequently use this acronym.
</para>
<para>
Once you've dealt with a bug report (e.g.  fixed it), mark it as
<literal>done</literal> (close it) by sending an explanation message to
<email><replaceable>123</replaceable>-done@&bugs-host;</email>.  If you're fixing a bug by changing
and uploading the package, you can automate bug closing as described in <xref
linkend="upload-bugfix"/>.
</para>
<para>
You should <emphasis>never</emphasis> close bugs via the bug server
<literal>close</literal> command sent to &email-bts-control;.
If you do so, the original submitter will not receive any information about why
the bug was closed.
</para>
</section>

<section id="bug-housekeeping">
<title>Bug housekeeping</title>
<para>
As a package maintainer, you will often find bugs in other packages or have
bugs reported against your packages which are actually bugs in other packages.
The bug tracking system's features are described in the <ulink
url="&url-bts-devel;">BTS documentation for Debian
developers</ulink>.  Operations such as reassigning, merging, and tagging bug
reports are described in the <ulink
url="&url-bts-control;">BTS control server
documentation</ulink>.  This section contains some guidelines for managing your
own bugs, based on the collective Debian developer experience.
</para>
<para>
Filing bugs for problems that you find in other packages is one of the civic
obligations of maintainership, see <xref linkend="submit-bug"/> for details.
However, handling the bugs in your own packages is even more important.
</para>
<para>
Here's a list of steps that you may follow to handle a bug report:
</para>
<orderedlist numeration="arabic">
<listitem>
<para>
Decide whether the report corresponds to a real bug or not.  Sometimes users
are just calling a program in the wrong way because they haven't read the
documentation.  If you diagnose this, just close the bug with enough
information to let the user correct their problem (give pointers to the good
documentation and so on).  If the same report comes up again and again you may
ask yourself if the documentation is good enough or if the program shouldn't
detect its misuse in order to give an informative error message.  This is an
issue that may need to be brought up with the upstream author.
</para>
<para>
If the bug submitter disagrees with your decision to close the bug, they may
reopen it until you find an agreement on how to handle it.  If you don't find
any, you may want to tag the bug <literal>wontfix</literal> to let people know
that the bug exists but that it won't be corrected.  If this situation is
unacceptable, you (or the submitter) may want to require a decision of the
technical committee by reassigning the bug to <systemitem
role="package">tech-ctte</systemitem> (you may use the clone command of the BTS
if you wish to keep it reported against your package).  Before doing so, please
read the <ulink url="&url-tech-ctte;">recommended
procedure</ulink>.
</para>
</listitem>
<listitem>
<para>
If the bug is real but it's caused by another package, just reassign the bug to
the right package.  If you don't know which package it should be reassigned to,
you should ask for help on <link linkend="irc-channels">IRC</link> or
on &email-debian-devel;.  Please inform the maintainer(s) of the package
you reassign the bug to, for example by Cc:ing the message that does the
reassign to <email><replaceable>packagename</replaceable>@packages.debian.org</email> and explaining
your reasons in that mail. Please note that a simple reassignment is
<emphasis>not</emphasis> e-mailed to the maintainers of the package
being reassigned to, so they won't know about it until they look at
a bug overview for their packages.
</para>
<para>
If the bug affects the operation of your package, please consider
cloning the bug and reassigning the clone to the package that really
causes the behavior. Otherwise, the bug will not be shown in your
package's bug list, possibly causing users to report the same bug over
and over again. You should block "your" bug with the reassigned, cloned
bug to document the relationship.
</para>
</listitem>
<listitem>
<para>
Sometimes you also have to adjust the severity of the bug so that it matches
our definition of the severity.  That's because people tend to inflate the
severity of bugs to make sure their bugs are fixed quickly.  Some bugs may even
be dropped to wishlist severity when the requested change is just cosmetic.
</para>
</listitem>
<listitem>
<para>
If the bug is real but the same problem has already been reported by someone
else, then the two relevant bug reports should be merged into one using the
merge command of the BTS.  In this way, when the bug is fixed, all of the
submitters will be informed of this.  (Note, however, that emails sent to one
bug report's submitter won't automatically be sent to the other report's
submitter.) For more details on the technicalities of the merge command and its
relative, the unmerge command, see the BTS control server documentation.
</para>
</listitem>
<listitem>
<para>
The bug submitter may have forgotten to provide some information, in which case
you have to ask them for the required information.  You may use the
<literal>moreinfo</literal> tag to mark the bug as such.  Moreover if you can't
reproduce the bug, you tag it <literal>unreproducible</literal>.  Anyone who
can reproduce the bug is then invited to provide more information on how to
reproduce it.  After a few months, if this information has not been sent by
someone, the bug may be closed.
</para>
</listitem>
<listitem>
<para>
If the bug is related to the packaging, you just fix it.  If you are not able
to fix it yourself, then tag the bug as <literal>help</literal>.  You can also
ask for help on &email-debian-devel; or
&email-debian-qa;.  If it's an upstream problem, you have to
forward it to the upstream author.  Forwarding a bug is not enough, you have to
check at each release if the bug has been fixed or not.  If it has, you just
close it, otherwise you have to remind the author about it.  If you have the
required skills you can prepare a patch that fixes the bug and send it to the
author at the same time.  Make sure to send the patch to the BTS and to tag the
bug as <literal>patch</literal>.
</para>
</listitem>
<listitem>
<para>
If you have fixed a bug in your local copy, or if a fix has been committed to
the VCS repository, you may tag the bug as <literal>pending</literal> to let
people know that the bug is corrected and that it will be closed with the next
upload (add the <literal>closes:</literal> in the
<filename>changelog</filename>).  This is particularly useful if you are
several developers working on the same package.
</para>
</listitem>
<listitem>
<para>
Once a corrected package is available in the archive, the bug should be
closed indicating the version in which it was fixed. This can be done
automatically, read <xref linkend="upload-bugfix"/>.
</para>
</listitem>
</orderedlist>
</section>

<section id="upload-bugfix">
<title>When bugs are closed by new uploads</title>
<para>
As bugs and problems are fixed in your packages, it is your responsibility as
the package maintainer to close these bugs.  However, you should not close a
bug until the package which fixes the bug has been accepted into the Debian
archive.  Therefore, once you get notification that your updated package has
been installed into the archive, you can and should close the bug in the BTS.
Also, the bug should be closed with the correct version.
</para>
<para>
However, it's possible to avoid having to manually close bugs after the upload
— just list the fixed bugs in your <filename>debian/changelog</filename>
file, following a certain syntax, and the archive maintenance software will
close the bugs for you.  For example:
</para>
<screen>
acme-cannon (3.1415) unstable; urgency=low

  * Frobbed with options (closes: Bug#98339)
  * Added safety to prevent operator dismemberment, closes: bug#98765,
    bug#98713, #98714.
  * Added man page. Closes: #98725.
</screen>
<para>
Technically speaking, the following Perl regular expression describes how bug
closing changelogs are identified:
</para>
<screen>
  /closes:\s*(?:bug)?\#\s*\d+(?:,\s*(?:bug)?\#\s*\d+)*/ig
</screen>
<para>
We prefer the <literal>closes: #<replaceable>XXX</replaceable></literal>
syntax, as it is the most concise entry and the easiest to integrate with the
text of the <filename>changelog</filename>.  Unless specified different by the
<literal>-v</literal>-switch to <command>dpkg-buildpackage</command>,
only the bugs closed in the most recent changelog entry are closed (basically,
exactly the bugs mentioned in the changelog-part in the
<filename>.changes</filename> file are closed).
</para>
<para>
Historically, uploads identified as <link linkend="nmu">non-maintainer
upload (NMU)</link> were tagged <literal>fixed</literal> instead of being
closed, but that practice was ceased with the advent of version-tracking.  The
same applied to the tag <literal>fixed-in-experimental</literal>.
</para>
<para>
If you happen to mistype a bug number or forget a bug in the changelog entries,
don't hesitate to undo any damage the error caused.  To reopen wrongly closed
bugs, send a <literal>reopen <replaceable>XXX</replaceable></literal> command
to the bug tracking system's control address,
&email-bts-control;.  To close any remaining bugs that were
fixed by your upload, email the <filename>.changes</filename> file to
<email><replaceable>XXX</replaceable>-done@&bugs-host;</email>, where <replaceable>XXX</replaceable>
is the bug number, and put Version: <replaceable>YYY</replaceable> and an empty line as the first two
lines of the body of the email, where <replaceable>YYY</replaceable> is the
first version where the bug has been fixed.
</para>
<para>
Bear in mind that it is not obligatory to close bugs using the changelog as
described above.  If you simply want to close bugs that don't have anything to
do with an upload you made, do it by emailing an explanation to
<email><replaceable>XXX</replaceable>-done@&bugs-host;</email>.  Do <emphasis
role="strong">not</emphasis> close bugs in the changelog entry of a version if
the changes in that version of the package don't have any bearing on the bug.
</para>
<para>
For general information on how to write your changelog entries, see <xref
linkend="bpp-debian-changelog"/>.
</para>
</section>

<section id="bug-security">
<title>Handling security-related bugs</title>
<para>
Due to their sensitive nature, security-related bugs must be handled carefully.
The Debian Security Team exists to coordinate this activity, keeping track of
outstanding security problems, helping maintainers with security problems or
fixing them themselves, sending security advisories, and maintaining
<literal>security.debian.org</literal>.
</para>
<para>
When you become aware of a security-related bug in a Debian package, whether or
not you are the maintainer, collect pertinent information about the problem,
and promptly contact the security team by emailing &email-security-team;. If
desired, email can be encrypted with the Debian Security Contact key, see
<ulink url="https://www.debian.org/security/faq#contact"/> for details.
<emphasis role="strong">DO NOT UPLOAD</emphasis> any packages for
<literal>stable</literal> without contacting the team.  Useful information
includes, for example:
</para>
<itemizedlist>
<listitem>
<para>
Whether or not the bug is already public.
</para>
</listitem>
<listitem>
<para>
Which versions of the package are known to be affected by the bug.  Check each
version that is present in a supported Debian release, as well as
<literal>testing</literal> and <literal>unstable</literal>.
</para>
</listitem>
<listitem>
<para>
The nature of the fix, if any is available (patches are especially helpful)
</para>
</listitem>
<listitem>
<para>
Any fixed packages that you have prepared yourself (send only the
<filename>.diff.gz</filename> and <filename>.dsc</filename> files and read <xref
linkend="bug-security-building"/> first)
</para>
</listitem>
<listitem>
<para>
Any assistance you can provide to help with testing (exploits, regression
testing, etc.)
</para>
</listitem>
<listitem>
<para>
Any information needed for the advisory (see <xref
linkend="bug-security-advisories"/>)
</para>
</listitem>
</itemizedlist>
<para>As the maintainer of the package, you have the responsibility to
maintain it, even in the stable release. You are in the best position
to evaluate patches and test updated packages, so please see the sections
below on how to prepare packages for the Security Team to handle.</para>

<section id="bug-security-tracker">
<title>The Security Tracker</title>
<para>
The security team maintains a central database, the
<ulink url="https://security-tracker.debian.org/">Debian Security Tracker</ulink>.
This contains all public information that is known about security issues:
which packages and versions are affected or fixed, and thus whether stable,
testing and/or unstable are vulnerable. Information that is still confidential
is not added to the tracker.
</para>
<para>
You can search it for a specific issue, but also on package name. Look
for your package to see which issues are still open. If you can, please provide
more information about those issues, or help to address them in your package.
Instructions are on the tracker web pages.
</para>
</section>

<section id="bug-security-confidentiality">
<title>Confidentiality</title>
<para>
Unlike most other activities within Debian, information about security issues
must sometimes be kept private for a time.  This allows software distributors
to coordinate their disclosure in order to minimize their users' exposure.
Whether this is the case depends on the nature of the problem and corresponding
fix, and whether it is already a matter of public knowledge.
</para>
<para>
There are several ways developers can learn of a security problem:
</para>
<itemizedlist>
<listitem>
<para>
they notice it on a public forum (mailing list, web site, etc.)
</para>
</listitem>
<listitem>
<para>
someone files a bug report
</para>
</listitem>
<listitem>
<para>
someone informs them via private email
</para>
</listitem>
</itemizedlist>
<para>
In the first two cases, the information is public and it is important to have a
fix as soon as possible.  In the last case, however, it might not be public
information.  In that case there are a few possible options for dealing with
the problem:
</para>
<itemizedlist>
<listitem>
<para>
If the security exposure is minor, there is sometimes no need to keep the
problem a secret and a fix should be made and released.
</para>
</listitem>
<listitem>
<para>
If the problem is severe, it is preferable to share the information with other
vendors and coordinate a release.  The security team keeps in contact with the
various organizations and individuals and can take care of that.
</para>
</listitem>
</itemizedlist>
<para>
In all cases if the person who reports the problem asks that it not be
disclosed, such requests should be honored, with the obvious exception of
informing the security team in order that a fix may be produced for a stable
release of Debian.  When sending confidential information to the security team,
be sure to mention this fact.
</para>
<para>
Please note that if secrecy is needed you may not upload a fix to
<literal>unstable</literal> (or
anywhere else, such as a public VCS repository).  It is not sufficient to
obfuscate the details of the change, as the code itself is public, and can (and
will) be examined by the general public.
</para>
<para>
There are two reasons for releasing information even though secrecy is
requested: the problem has been known for a while, or the problem or exploit
has become public.
</para>
<para>
The Security Team has a PGP-key to enable encrypted communication about
sensitive issues. See the <ulink url="https://www.debian.org/security/faq#contact">Security Team FAQ</ulink> for details.
</para>
</section>

<section id="bug-security-advisories">
<title>Security Advisories</title>
<para>
Security advisories are only issued for the current, released stable
distribution, and <emphasis>not</emphasis> for <literal>testing</literal>
or <literal>unstable</literal>.  When released, advisories are sent to the
&email-debian-security-announce; mailing list and posted on
<ulink url="&url-debian-security-advisories;">the security web
page</ulink>.  Security advisories are written and posted by the security team.
However they certainly do not mind if a maintainer can supply some of the
information for them, or write part of the text.  Information that should be in
an advisory includes:
</para>
<itemizedlist>
<listitem>
<para>
A description of the problem and its scope, including:
</para>
<itemizedlist>
<listitem>
<para>
The type of problem (privilege escalation, denial of service, etc.)
</para>
</listitem>
<listitem>
<para>
What privileges may be gained, and by whom (if any)
</para>
</listitem>
<listitem>
<para>
How it can be exploited
</para>
</listitem>
<listitem>
<para>
Whether it is remotely or locally exploitable
</para>
</listitem>
<listitem>
<para>
How the problem was fixed
</para>
</listitem>
</itemizedlist>
<para>
This information allows users to assess the threat to their systems.
</para>
</listitem>
<listitem>
<para>
Version numbers of affected packages
</para>
</listitem>
<listitem>
<para>
Version numbers of fixed packages
</para>
</listitem>
<listitem>
<para>
Information on where to obtain the updated packages (usually from the Debian
security archive)
</para>
</listitem>
<listitem>
<para>
References to upstream advisories, <ulink
url="https://cve.mitre.org">CVE</ulink> identifiers, and any other information
useful in cross-referencing the vulnerability
</para>
</listitem>
</itemizedlist>
</section>

<section id="bug-security-building">
<title>Preparing packages to address security issues</title>
<para>
One way that you can assist the security team in their duties is to provide
them with fixed packages suitable for a security advisory for the stable Debian
release.
</para>
<para>
When an update is made to the stable release, care must be taken to avoid
changing system behavior or introducing new bugs.  In order to do this, make as
few changes as possible to fix the bug.  Users and administrators rely on the
exact behavior of a release once it is made, so any change that is made might
break someone's system.  This is especially true of libraries: make sure you
never change the API or ABI, no matter how small the change.
</para>
<para>
This means that moving to a new upstream version is not a good solution.
Instead, the relevant changes should be back-ported to the version present in
the current stable Debian release.  Generally, upstream maintainers are willing
to help if needed.  If not, the Debian security team may be able to help.
</para>
<para>
In some cases, it is not possible to back-port a security fix, for example when
large amounts of source code need to be modified or rewritten.  If this
happens, it may be necessary to move to a new upstream version.  However, this
is only done in extreme situations, and you must always coordinate that with
the security team beforehand.
</para>
<para>
Related to this is another important guideline: always test your changes.  If
you have an exploit available, try it and see if it indeed succeeds on the
unpatched package and fails on the fixed package.  Test other, normal actions
as well, as sometimes a security fix can break seemingly unrelated features in
subtle ways.
</para>
<para>
Do <emphasis role="strong">NOT</emphasis> include any changes in your package
which are not directly related to fixing the vulnerability.  These will only
need to be reverted, and this wastes time.  If there are other bugs in your
package that you would like to fix, make an upload to proposed-updates in the
usual way, after the security advisory is issued.  The security update
mechanism is not a means for introducing changes to your package which would
otherwise be rejected from the stable release, so please do not attempt to do
this.
</para>
<para>
Review and test your changes as much as possible.  Check the differences from
the previous version repeatedly (<command>interdiff</command> from the
<systemitem role="package">patchutils</systemitem> package and
<command>debdiff</command> from <systemitem
role="package">devscripts</systemitem> are useful tools for this, see <xref
linkend="debdiff"/>).
</para>
<para>
Be sure to verify the following items:
</para>
<itemizedlist>
<listitem>
<para>
<emphasis role="strong">Target the right distribution</emphasis>
in your <filename>debian/changelog</filename>:
<replaceable>codename</replaceable><literal>-security</literal>
(e.g. <literal>wheezy-security</literal>).
Do not target <replaceable>distribution</replaceable><literal>-proposed-updates</literal> or
<literal>stable</literal>!
</para>
</listitem>
<listitem>
<para>
The upload should have <emphasis role="strong">urgency=high</emphasis>.
</para>
</listitem>
<listitem>
<para>
Make descriptive, meaningful changelog entries.  Others will rely on them to
determine whether a particular bug was fixed.  Add <literal>closes:</literal>
statements for any <emphasis role="strong">Debian bugs</emphasis> filed.
Always include an external reference, preferably a <emphasis role="strong">CVE
identifier</emphasis>, so that it can be cross-referenced. However, if a CVE
identifier has not yet been assigned, do not wait for it but continue the
process. The identifier can be cross-referenced later.
</para>
</listitem>
<listitem>
<para>
Make sure the <emphasis role="strong">version number</emphasis> is proper.
It must be greater than the current package, but less than package versions in
later distributions.  If in doubt, test it with <literal>dpkg
--compare-versions</literal>.  Be careful not to re-use a version number that
you have already used for a previous upload, or one that conflicts with a
binNMU. The convention is to append
<literal>+deb</literal><replaceable>X</replaceable><literal>u1</literal> (where
<replaceable>X</replaceable> is the major release number), e.g.
<literal>1:2.4.3-4+deb7u1</literal>, of course increasing 1 for any subsequent
uploads.
</para>
</listitem>
<listitem>
<para>
Unless the upstream source has been uploaded to
<literal>security.debian.org</literal> before (by a previous security update),
build the upload <emphasis role="strong">with full upstream source</emphasis>
(<literal>dpkg-buildpackage -sa</literal>).  If there has been a previous
upload to <literal>security.debian.org</literal> with the same upstream
version, you may upload without upstream source (<literal>dpkg-buildpackage
-sd</literal>).
</para>
</listitem>
<listitem>
<para>
Be sure to use the <emphasis role="strong">exact same
<filename>*.orig.tar.{gz,bz2,xz}</filename></emphasis> as used in the
normal archive, otherwise it is not possible to move the security fix into the
main archives later.
</para>
</listitem>
<listitem>
<para>
Build the package on a <emphasis role="strong">clean system</emphasis> which only
has packages installed from the distribution you are building for. If you do not
have such a system yourself, you can use a debian.org machine (see
<xref linkend="server-machines"/>) or setup a chroot (see
<xref linkend="pbuilder"/> and <xref linkend="debootstrap"/>).
</para>
</listitem>
</itemizedlist>
</section>

<section id="bug-security-upload">
<title>Uploading the fixed package</title>
<para>
Do <emphasis role="strong">NOT</emphasis> upload a package to the security
upload queue (on <literal>security-master.debian.org</literal>)
without prior authorization from the security team.  If the
package does not exactly meet the team's requirements, it will cause many
problems and delays in dealing with the unwanted upload.
</para>
<para>
Do <emphasis role="strong">NOT</emphasis> upload your fix to
<literal>proposed-updates</literal> without coordinating with the security team.
Packages from <literal>security.debian.org</literal> will be copied into
the <literal>proposed-updates</literal> directory automatically.  If a package
with the same or a higher version number is already installed into the archive,
the security update will be rejected by the archive system.  That way, the
stable distribution will end up without a security update for this package
instead.
</para>
<para>
Once you have created and tested the new package and it has been approved by
the security team, it needs to be uploaded so that it can be installed in the
archives.  For security uploads, the place to upload to is
<literal>ftp://security-master.debian.org/pub/SecurityUploadQueue/</literal>.
</para>
<para>
Once an upload to the security queue has been accepted, the package will
automatically be built for all architectures and stored for verification by
the security team.
</para>
<para>
Uploads which are waiting for acceptance or verification are only accessible by
the security team.  This is necessary since there might be fixes for security
problems that cannot be disclosed yet.
</para>
<para>
If a member of the security team accepts a package, it will be installed on
<literal>security.debian.org</literal> as well as proposed for the proper
<replaceable>distribution</replaceable><literal>-proposed-updates</literal>
on <literal>&ftp-master-host;</literal>.
</para>
</section>

</section>

</section>

<section id="archive-manip">
<title>Moving, removing, renaming, orphaning, adopting, and reintroducing packages</title>
<para>
Some archive manipulation operations are not automated in the Debian upload
process.  These procedures should be manually followed by maintainers.  This
chapter gives guidelines on what to do in these cases.
</para>
<section id="moving-pkgs">
<title>Moving packages</title>
<para>
Sometimes a package will change its section.  For instance, a package from the
<literal>non-free</literal> section might be GPL'd in a later version, in which case the package
should be moved to `main' or `contrib'.<footnote><para> See the <ulink
url="&url-debian-policy;">Debian Policy Manual</ulink> for
guidelines on what section a package belongs in.  </para> </footnote>
</para>
<para>
If you need to change the section for one of your packages, change the package
control information to place the package in the desired section, and re-upload
the package (see the <ulink
url="&url-debian-policy;">Debian Policy Manual</ulink> for
details).  You must ensure that you include the
<filename>.orig.tar.{gz,bz2,xz}</filename> in your upload (even if you are not uploading
a new upstream version), or it will not appear in the new section together with
the rest of the package.  If your new section is valid, it will be moved
automatically.  If it does not, then contact the ftpmasters in order to
understand what happened.
</para>
<para>
If, on the other hand, you need to change the <literal>subsection</literal>
of one of your packages (e.g., ``devel'', ``admin''), the procedure is slightly
different.  Correct the subsection as found in the control file of the package,
and re-upload that.  Also, you'll need to get the override file updated, as
described in <xref linkend="override-file"/>.
</para>
</section>

<section id="removing-pkgs">
<title>Removing packages</title>
<para>
If for some reason you want to completely remove a package (say, if it is an
old compatibility library which is no longer required), you need to file a bug
against <systemitem role="package">&ftp-debian-org;</systemitem> asking that the package be removed;
as all bugs, this bug should normally have normal severity.
The bug title should be in the form <literal>RM: <replaceable>package</replaceable>
<replaceable>[architecture list]</replaceable> --
<replaceable>reason</replaceable></literal>, where <replaceable>package</replaceable>
is the package to be removed and <replaceable>reason</replaceable> is a
short summary of the reason for the removal request.
<replaceable>[architecture list]</replaceable> is optional and only needed
if the removal request only applies to some architectures, not all. Note
that the <command>reportbug</command> will create a title conforming
to these rules when you use it to report a bug against the
<systemitem role="package">&ftp-debian-org;</systemitem> pseudo-package.
</para>

<para>
If you want to remove a package you maintain, you should note this in
the bug title by prepending <literal>ROM</literal> (Request Of Maintainer).
There are several other standard acronyms used in the reasoning for a package
removal, see <ulink url="https://&ftp-master-host;/removals.html"></ulink>
for a complete list. That page also provides a convenient overview of
pending removal requests.
</para>

<para>
Note that removals can only be done for the <literal>unstable</literal>,
<literal>experimental</literal> and <literal>stable</literal>
distribution.  Packages are not removed from
<literal>testing</literal> directly.  Rather, they will be removed
automatically after the package has been removed from
<literal>unstable</literal> and no package in
<literal>testing</literal> depends on it. (Removals from
<literal>testing</literal> are possible though by filing a removal bug report
against the <systemitem role="package">&release-debian-org;</systemitem>
pseudo-package. See the section <xref linkend="removals"/>.)
</para>
<para>
There is one exception when an explicit removal request is not necessary: If a
(source or binary) package is no longer built from source, it will be removed
semi-automatically. For a binary-package, this means if there is no longer any
source package producing this binary package; if the binary package is just no
longer produced on some architectures, a removal request is still necessary. For
a source-package, this means that all binary packages it refers to have been
taken over by another source package.
</para>
<para>
In your removal request, you have to detail the reasons justifying the request.
This is to avoid unwanted removals and to keep a trace of why a package has
been removed.  For example, you can provide the name of the package that
supersedes the one to be removed.
</para>
<para>
Usually you only ask for the removal of a package maintained by yourself.  If
you want to remove another package, you have to get the approval of its
maintainer. Should the package be orphaned and thus have no maintainer,
you should first discuss the removal request on &email-debian-qa;. If
there is a consensus that the package should be removed, you should
reassign and retitle the <literal>O:</literal> bug filed against the
<literal>wnpp</literal> package instead of filing a new bug as
removal request.
</para>
<para>
Further information relating to these and other package removal related topics
may be found at <ulink url="https://wiki.debian.org/ftpmaster_Removals"></ulink>
and <ulink url="&url-debian-qa;howto-remove.html"></ulink>.
</para>
<para>
If in doubt concerning whether a package is disposable, email
&email-debian-devel; asking for opinions.  Also of interest is
the <command>apt-cache</command> program from the <systemitem
role="package">apt</systemitem> package.  When invoked as <literal>apt-cache
showpkg <replaceable>package</replaceable></literal>, the program will show
details for <replaceable>package</replaceable>, including reverse depends.
Other useful programs include <command>apt-cache rdepends</command>,
<command>apt-rdepends</command>, <command>build-rdeps</command> (in the
<systemitem role="package">devscripts</systemitem> package) and
<command>grep-dctrl</command>.  Removal of
orphaned packages is discussed on &email-debian-qa;.
</para>
<para>
Once the package has been removed, the package's bugs should be handled.  They
should either be reassigned to another package in the case where the actual
code has evolved into another package (e.g.  <literal>libfoo12</literal> was
removed because <literal>libfoo13</literal> supersedes it) or closed if the
software is simply no longer part of Debian.
When closing the bugs,
to avoid marking the bugs as fixed in versions of the packages
in previous Debian releases, they should be marked as fixed
in the version <literal>&lt;most-recent-version-ever-in-Debian&gt;+rm</literal>.
</para>
<section id="s5.9.2.1">
<title>Removing packages from <filename>Incoming</filename></title>
<para>
In the past, it was possible to remove packages from
<filename>incoming</filename>.  However, with the introduction of the new
incoming system, this is no longer possible.  Instead, you have to upload a new
revision of your package with a higher version than the package you want to
replace.  Both versions will be installed in the archive but only the higher
version will actually be available in <literal>unstable</literal> since the
previous version will immediately be replaced by the higher.  However, if you
do proper testing of your packages, the need to replace a package should not
occur too often anyway.
</para>
</section>

</section>

<section id="s5.9.3">
<title>Replacing or renaming packages</title>
<para>
When the upstream maintainers for one of your packages chose to
rename their software (or you made a mistake naming your package),
you should follow a two-step process to rename it. In the first
step, change the <filename>debian/control</filename> file to
reflect the new name and to replace, provide and conflict with the
obsolete package name (see the <ulink url="&url-debian-policy;">Debian
Policy Manual</ulink> for details).  Please note that you
should only add a <literal>Provides</literal> relation if all
packages depending on the obsolete package name continue to work
after the renaming. Once you've uploaded the package and the package
has moved into the archive, file a bug against <systemitem role="package">&ftp-debian-org;</systemitem>
asking to remove the package with the
obsolete name (see <xref linkend="removing-pkgs"/>).  Do not forget
to properly reassign the package's bugs at the same time.
</para>
<para>
At other times, you may make a mistake in constructing your package and wish to
replace it.  The only way to do this is to increase the version number and
upload a new version.  The old version will be expired in the usual manner.
Note that this applies to each part of your package, including the sources: if
you wish to replace the upstream source tarball of your package, you will need
to upload it with a different version.  An easy possibility is to replace
<filename>foo_1.00.orig.tar.gz</filename> with
<filename>foo_1.00+0.orig.tar.gz</filename> or
<filename>foo_1.00.orig.tar.bz2</filename>.  This restriction gives each
file on the ftp site a unique name, which helps to ensure consistency
across the mirror network.
</para>
</section>

<section id="orphaning">
<title>Orphaning a package</title>
<para>
If you can no longer maintain a package, you need to inform others, and see
that the package is marked as orphaned.  You should set the package maintainer
to <literal>Debian QA Group &orphan-address;</literal> and
submit a bug report against the pseudo package <systemitem
role="package">wnpp</systemitem>.  The bug report should be titled <literal>O:
<replaceable>package</replaceable> -- <replaceable>short
description</replaceable></literal> indicating that the package is now
orphaned.  The severity of the bug should be set to
<literal>normal</literal>; if the package has a priority of standard or
higher, it should be set to important.  If you feel it's necessary, send a copy
to &email-debian-devel; by putting the address in the
X-Debbugs-CC: header of the message (no, don't use CC:, because that way the
message's subject won't indicate the bug number).
</para>
<para>
If you just intend to give the package away, but you can keep maintainership
for the moment, then you should instead submit a bug against <systemitem
role="package">wnpp</systemitem> and title it <literal>RFA:
<replaceable>package</replaceable> -- <replaceable>short
description</replaceable></literal>.  <literal>RFA</literal> stands for
<literal>Request For Adoption</literal>.
</para>
<para>
More information is on the <ulink url="&url-wnpp;">WNPP
web pages</ulink>.
</para>
</section>

<section id="adopting">
<title>Adopting a package</title>
<para>
A list of packages in need of a new maintainer is available in the <ulink
url="&url-wnpp;">Work-Needing and Prospective Packages
list (WNPP)</ulink>.  If you wish to take over maintenance of any of the
packages listed in the WNPP, please take a look at the aforementioned page for
information and procedures.
</para>
<para>
It is not OK to simply take over a package that you feel is neglected — that
would be package hijacking.  You can, of course, contact the current maintainer
and ask them if you may take over the package.  If you have reason to believe a
maintainer has gone AWOL (absent without leave), see <xref linkend="mia-qa"/>.
</para>
<para>
Generally, you may not take over the package without the assent of the current
maintainer.  Even if they ignore you, that is still not grounds to take over a
package.  Complaints about maintainers should be brought up on the developers'
mailing list.  If the discussion doesn't end with a positive conclusion, and
the issue is of a technical nature, consider bringing it to the attention of
the technical committee (see the <ulink
url="&url-tech-ctte;">technical committee web page</ulink> for
more information).
</para>
<para>
If you take over an old package, you probably want to be listed as the
package's official maintainer in the bug system.  This will happen
automatically once you upload a new version with an updated
<literal>Maintainer</literal> field, although it can take a few hours after
the upload is done.  If you do not expect to upload a new version for a while,
you can use <xref linkend="pkg-tracking-system"/> to get the bug reports.
However, make sure that the old maintainer has no problem with the fact that
they will continue to receive the bugs during that time.
</para>
</section>

<section id="reintroducing-pkgs">
<title>Reintroducing packages</title>
<para>
Packages are often removed due to release-critical bugs, absent maintainers,
too few users or poor quality in general. While the process of reintroduction
is similar to the initial packaging process, you can avoid some pitfalls by
doing some historical research first.
</para>
<para>
You should check why the package was removed in the first place. This
information can be found in the removal item in the news section of the PTS
page for the package or by browsing the log of
<ulink url="https://&ftp-master-host;/#removed">removals</ulink>.
The removal bug will tell you why the package was removed and will give some
indication of what you will need to work on in order to reintroduce the package.
It may indicate that the best way forward is to switch to some other piece of
software instead of reintroducing the package.
</para>
<para>
It may be appropriate to contact the former maintainers to find out if
they are working on reintroducing the package, interested in co-maintaining
the package or interested in sponsoring the package if needed.
</para>
<para>
You should do all the things required before introducing new packages
(<xref linkend="newpackage"/>).
</para>
<para>
You should base your work on the latest packaging available that is suitable.
That might be the latest version from <literal>unstable</literal>, which will
still be present in the <ulink url="&snap-debian-org;">snapshot archive</ulink>.
</para>
<para>
The version control system used by the previous maintainer might contain useful
changes, so it might be a good idea to have a look there.  Check if the <filename>control</filename>
file of the previous package contained any headers linking to the version
control system for the package and if it still exists.
</para>
<para>
Package removals from <literal>unstable</literal> (not <literal>testing</literal>,
<literal>stable</literal> or <literal>oldstable</literal>) trigger the
closing of all bugs related to the package. You should look through all the
closed bugs (including archived bugs) and unarchive and reopen any that were
closed in a version ending in <literal>+rm</literal> and still apply. Any that
no longer apply should be marked as fixed in the correct version if that is
known.
</para>
</section>

</section>

<section id="porting">
<title>Porting and being ported</title>
<para>
Debian supports an ever-increasing number of architectures.  Even if you are
not a porter, and you don't use any architecture but one, it is part of your
duty as a maintainer to be aware of issues of portability.  Therefore, even if
you are not a porter, you should read most of this chapter.
</para>
<para>
Porting is the act of building Debian packages for architectures that are
different from the original architecture of the package maintainer's binary
package.  It is a unique and essential activity.  In fact, porters do most of
the actual compiling of Debian packages.  For instance, when a maintainer
uploads a (portable) source packages with binaries for the <literal>i386</literal>
architecture, it will be built for each of the other architectures,
amounting to &number-of-arches; more builds.
</para>
<section id="kind-to-porters">
<title>Being kind to porters</title>
<para>
Porters have a difficult and unique task, since they are required to deal with
a large volume of packages.  Ideally, every source package should build right
out of the box.  Unfortunately, this is often not the case.  This section
contains a checklist of ``gotchas'' often committed by Debian maintainers —
common problems which often stymie porters, and make their jobs unnecessarily
difficult.
</para>
<para>
The first and most important thing is to respond quickly to bug or issues
raised by porters.  Please treat porters with courtesy, as if they were in fact
co-maintainers of your package (which, in a way, they are).  Please be tolerant
of succinct or even unclear bug reports; do your best to hunt down whatever the
problem is.
</para>
<para>
By far, most of the problems encountered by porters are caused by
<emphasis>packaging bugs</emphasis> in the source packages.  Here is a
checklist of things you should check or be aware of.
</para>
<orderedlist numeration="arabic">
<listitem>
<para>
Make sure that your <literal>Build-Depends</literal> and
<literal>Build-Depends-Indep</literal> settings in
<filename>debian/control</filename> are set properly.  The best way to validate
this is to use the <systemitem role="package">debootstrap</systemitem> package
to create an <literal>unstable</literal> chroot environment (see <xref
linkend="debootstrap"/>).
Within that chrooted environment, install the <systemitem
role="package">build-essential</systemitem> package and any package
dependencies mentioned in <literal>Build-Depends</literal> and/or
<literal>Build-Depends-Indep</literal>.  Finally, try building your package
within that chrooted environment.  These steps can be automated by the use of
the <command>pbuilder</command> program which is provided by the package of the
same name (see <xref linkend="pbuilder"/>).
</para>
<para>
If you can't set up a proper chroot, <command>dpkg-depcheck</command> may be of
assistance (see <xref linkend="dpkg-depcheck"/>).
</para>
<para>
See the <ulink url="&url-debian-policy;">Debian Policy
Manual</ulink> for instructions on setting build dependencies.
</para>
</listitem>
<listitem>
<para>
Don't set architecture to a value other than <literal>all</literal> or
<literal>any</literal> unless you really mean it.  In too many cases,
maintainers don't follow the instructions in the <ulink
url="&url-debian-policy;">Debian Policy Manual</ulink>.  Setting your
architecture to only one architecture (such as <literal>i386</literal>
or <literal>amd64</literal>) is usually incorrect.
</para>
</listitem>
<listitem>
<para>
Make sure your source package is correct.  Do <literal>dpkg-source -x
<replaceable>package</replaceable>.dsc</literal> to make sure your source
package unpacks properly.  Then, in there, try building your package from
scratch with <command>dpkg-buildpackage</command>.
</para>
</listitem>
<listitem>
<para>
Make sure you don't ship your source package with the
<filename>debian/files</filename> or <filename>debian/substvars</filename>
files.  They should be removed by the <literal>clean</literal> target of
<filename>debian/rules</filename>.
</para>
</listitem>
<listitem>
<para>
Make sure you don't rely on locally installed or hacked configurations or
programs.  For instance, you should never be calling programs in
<filename>/usr/local/bin</filename> or the like.  Try not to rely on programs
being setup in a special way.  Try building your package on another machine,
even if it's the same architecture.
</para>
</listitem>
<listitem>
<para>
Don't depend on the package you're building being installed already (a sub-case
of the above issue). There are, of course, exceptions to this rule, but be
aware that any case like this needs manual bootstrapping and cannot be done
by automated package builders.
</para>
</listitem>
<listitem>
<para>
Don't rely on the compiler being a certain version, if possible.  If not, then
make sure your build dependencies reflect the restrictions, although you are
probably asking for trouble, since different architectures sometimes
standardize on different compilers.
</para>
</listitem>
<listitem>
<para>
Make sure your <filename>debian/rules</filename> contains separate <literal>binary-arch</literal>
and <literal>binary-indep</literal> targets, as the Debian Policy Manual
requires.  Make sure that both targets work independently, that is, that you
can call the target without having called the other before.  To test this,
try to run <command>dpkg-buildpackage -B</command>.
</para>
</listitem>
</orderedlist>
</section>

<section id="porter-guidelines">
<title>Guidelines for porter uploads</title>
<para>
If the package builds out of the box for the architecture to be ported to, you
are in luck and your job is easy.  This section applies to that case; it
describes how to build and upload your binary package so that it is properly
installed into the archive.  If you do have to patch the package in order to
get it to compile for the other architecture, you are actually doing a source
NMU, so consult <xref linkend="nmu-guidelines"/> instead.
</para>
<para>
For a porter upload, no changes are being made to the source.  You do not need
to touch any of the files in the source package.  This includes
<filename>debian/changelog</filename>.
</para>
<para>
The way to invoke <command>dpkg-buildpackage</command> is as
<literal>dpkg-buildpackage -B
-m<replaceable>porter-email</replaceable></literal>.  Of course, set
<replaceable>porter-email</replaceable> to your email address.  This will do a
binary-only build of only the architecture-dependent portions of the package,
using the <literal>binary-arch</literal> target in
<filename>debian/rules</filename>.
</para>
<para>
If you are working on a Debian machine for your porting efforts and you need to
sign your upload locally for its acceptance in the archive, you can run
<command>debsign</command> on your <filename>.changes</filename> file to have
it signed conveniently, or use the remote signing mode of
<command>dpkg-sig</command>.
</para>
<section id="binary-only-nmu">
<title>Recompilation or binary-only NMU</title>
<para>
Sometimes the initial porter upload is problematic because the environment in
which the package was built was not good enough (outdated or obsolete library,
bad compiler, etc.).  Then you may just need to recompile it in an updated
environment.  However, you have to bump the version number in this case, so
that the old bad package can be replaced in the Debian archive
(<command>dak</command> refuses to install new packages if they don't have a
version number greater than the currently available one).
</para>
<para>
You have to make sure that your binary-only NMU doesn't render the package
uninstallable.  This could happen when a source package generates
arch-dependent and arch-independent packages that have inter-dependencies
generated using dpkg's substitution variable <literal>$(Source-Version)</literal>.
</para>
<para>
Despite the required modification of the changelog, these are called
binary-only NMUs — there is no need in this case to trigger all other
architectures to consider themselves out of date or requiring recompilation.
</para>
<para>
Such recompilations require special ``magic'' version numbering, so that the
archive maintenance tools recognize that, even though there is a new Debian
version, there is no corresponding source update.  If you get this wrong, the
archive maintainers will reject your upload (due to lack of corresponding
source code).
</para>
<para>
The ``magic'' for a recompilation-only NMU is triggered by using a suffix
appended to the package version number, following the form
<literal>b<replaceable>number</replaceable></literal>.
For instance, if the latest version you are recompiling against was version
<literal>2.9-3</literal>, your binary-only NMU should carry a version of
<literal>2.9-3+b1</literal>.  If the latest version was <literal>3.4+b1</literal>
(i.e, a native package with a previous recompilation NMU), your
binary-only NMU should have a version number of <literal>3.4+b2</literal>.<footnote><para>
In the past, such NMUs used the third-level number on the
Debian part of the revision to denote their recompilation-only status;
however, this syntax was ambiguous with native packages and did not allow
proper ordering of recompile-only NMUs, source NMUs, and security NMUs on
the same package, and has therefore been abandoned in favor of this new syntax.
</para> </footnote>
</para>
<para>
Similar to initial porter uploads, the correct way of invoking
<command>dpkg-buildpackage</command> is <literal>dpkg-buildpackage -B</literal>
to only build the architecture-dependent parts of the package.
</para>
</section>

<section id="source-nmu-when-porter">
<title>When to do a source NMU if you are a porter</title>
<para>
Porters doing a source NMU generally follow the guidelines found in <xref
linkend="nmu"/>, just like non-porters.  However, it is expected that the wait
cycle for a porter's source NMU is smaller than for a non-porter, since porters
have to cope with a large quantity of packages.  Again, the situation varies
depending on the distribution they are uploading to.  It also varies whether
the architecture is a candidate for inclusion into the next stable release; the
release managers decide and announce which architectures are candidates.
</para>
<para>
If you are a porter doing an NMU for <literal>unstable</literal>, the above
guidelines for porting should be followed, with two variations.  Firstly, the
acceptable waiting period — the time between when the bug is submitted to
the BTS and when it is OK to do an NMU — is seven days for porters working
on the <literal>unstable</literal> distribution.  This period can be shortened
if the problem is critical and imposes hardship on the porting effort, at the
discretion of the porter group.  (Remember, none of this is Policy, just
mutually agreed upon guidelines.) For uploads to <literal>stable</literal> or
<literal>testing</literal>, please coordinate with the appropriate release
team first.
</para>
<para>
Secondly, porters doing source NMUs should make sure that the bug they submit
to the BTS should be of severity <literal>serious</literal> or greater.  This
ensures that a single source package can be used to compile every supported
Debian architecture by release time.  It is very important that we have one
version of the binary and source package for all architectures in order to
comply with many licenses.
</para>
<para>
Porters should try to avoid patches which simply kludge around bugs in the
current version of the compile environment, kernel, or libc.  Sometimes such
kludges can't be helped.  If you have to kludge around compiler bugs and the
like, make sure you <literal>#ifdef</literal> your work properly; also,
document your kludge so that people know to remove it once the external
problems have been fixed.
</para>
<para>
Porters may also have an unofficial location where they can put the results of
their work during the waiting period.  This helps others running the port have
the benefit of the porter's work, even during the waiting period.  Of course,
such locations have no official blessing or status, so buyer beware.
</para>
</section>

</section>

<section id="porter-automation">
<title>Porting infrastructure and automation</title>
<para>
There is infrastructure and several tools to help automate package porting.
This section contains a brief overview of this automation and porting to these
tools; see the package documentation or references for full information.
</para>
<section id="s5.10.3.1">
<title>Mailing lists and web pages</title>
<para>
Web pages containing the status of each port can be found at <ulink
url="&url-debian-ports;"></ulink>.
</para>
<para>
Each port of Debian has a mailing list.  The list of porting mailing lists can
be found at <ulink url="&url-debian-port-lists;"></ulink>.  These
lists are used to coordinate porters, and to connect the users of a given port
with the porters.
</para>
</section>

<section id="s5.10.3.2">
<title>Porter tools</title>
<para>
Descriptions of several porting tools can be found in <xref
linkend="tools-porting"/>.
</para>
</section>

<section id="wanna-build">
<title><systemitem role="package">wanna-build</systemitem></title>
<para>
The <systemitem role="package">wanna-build</systemitem> system is used as a
distributed, client-server build distribution system.  It is usually used in
conjunction with build daemons running the <systemitem role="package">buildd</systemitem>
program. <literal>Build daemons</literal> are ``slave'' hosts
which contact the central <systemitem role="package">wanna-build</systemitem>
system to receive a list of packages that need to be built.
</para>
<para>
<systemitem role="package">wanna-build</systemitem> is not yet available as a
package; however, all Debian porting efforts are using it for automated
package building.  The tool used to do the actual package builds, <systemitem
role="package">sbuild</systemitem> is available as a package, see its
description in <xref linkend="sbuild"/>.  Please note that the packaged
version is not the same as the one used on build daemons, but it is close
enough to reproduce problems.
</para>
<para>
Most of the data produced by <systemitem role="package">wanna-build</systemitem>
which is generally useful to porters is available on the
web at <ulink url="&url-buildd;"></ulink>.  This data includes nightly
updated statistics, queueing information and logs for build attempts.
</para>
<para>
We are quite proud of this system, since it has so many possible uses.
Independent development groups can use the system for different sub-flavors of
Debian, which may or may not really be of general interest (for instance, a
flavor of Debian built with <command>gcc</command> bounds checking).  It will
also enable Debian to recompile entire distributions quickly.
</para>
<para>
The wanna-build team, in charge of the buildds,
can be reached at <literal>debian-wb-team@lists.debian.org</literal>.
To determine who (wanna-build team, release team) and how (mail, BTS)
to contact, refer to <ulink url="&url-wb-team;"></ulink>.
</para>

<para>
When requesting binNMUs or give-backs (retries after a failed build),
please use the format described at <ulink url="&url-release-wb;"/>.
</para>

</section>

</section>

<section id="packages-arch-specific">
<title>When your package is <emphasis>not</emphasis> portable</title>
<para>
Some packages still have issues with building and/or working on some of the
architectures supported by Debian, and cannot be ported at all, or not within a
reasonable amount of time.  An example is a package that is SVGA-specific (only
available for <literal>i386</literal> and <literal>amd64</literal>), or uses
other hardware-specific features not supported on all architectures.
</para>
<para>
In order to prevent broken packages from being uploaded to the archive, and
wasting buildd time, you need to do a few things:
</para>
<itemizedlist>
<listitem>
<para>
First, make sure your package <emphasis>does</emphasis> fail to build on
architectures that it cannot support.  There are a few ways to achieve this.
The preferred way is to have a small testsuite during build time that will test
the functionality, and fail if it doesn't work.  This is a good idea anyway, as
this will prevent (some) broken uploads on all architectures, and also will
allow the package to build as soon as the required functionality is available.
</para>
<para>
Additionally, if you believe the list of supported architectures is pretty
constant, you should change <literal>any</literal> to a list of supported
architectures in <filename>debian/control</filename>.  This way, the build will
fail also, and indicate this to a human reader without actually trying.
</para>
</listitem>
<listitem>
<para>
In order to prevent autobuilders from needlessly trying to build your package,
it must be included in <filename>Packages-arch-specific</filename>, a list used
by the <command>wanna-build</command> script.  The current version is available
as <ulink url="&url-buildd-p-a-s;"/>;
please see the top of the file for whom to contact for changes.
</para>
</listitem>
</itemizedlist>
<para>
Please note that it is insufficient to only add your package to
<filename>Packages-arch-specific</filename> without making it fail to build on unsupported
architectures: A porter or any other person trying to build your package might
accidently upload it without noticing it doesn't work.  If in the past some
binary packages were uploaded on unsupported architectures, request their
removal by filing a bug against <systemitem
role="package">ftp.debian.org</systemitem>.
</para>
</section>

<section id="non-free-buildd">
<title>Marking non-free packages as auto-buildable</title>
<para>
By default packages from the <literal>non-free</literal> section are not built by the autobuilder
network (mostly because the license of the packages could disapprove).
To enable a package to be build you need to perform the following
steps:
</para>
<orderedlist numeration="arabic">
<listitem>
<para>
Check whether it is legally allowed and technically possible
to auto-build the package;
</para>
</listitem>
<listitem>
<para>
Add <literal>XS-Autobuild: yes</literal> into the header part
of <filename>debian/control</filename>;
</para>
</listitem>
<listitem>
<para>
Send an email to &email-nonfree-release; and explain why the
package can legitimately and technically be auto-built.
</para>
</listitem>
</orderedlist>
</section>
</section>

<section id="nmu">
<title>Non-Maintainer Uploads (NMUs)</title>
<para>
Every package has one or more maintainers. Normally, these are the people who
work on and upload new versions of the package. In some situations, it is
useful that other developers can upload a new version as well, for example if
they want to fix a bug in a package they don't maintain, when the maintainer
needs help to respond to issues.  Such uploads are called
<emphasis>Non-Maintainer Uploads (NMU)</emphasis>.
</para>

<section id="nmu-guidelines">
<title>When and how to do an NMU</title>

<para>
Before doing an NMU, consider the following questions:
</para>
<itemizedlist>
<listitem>
<para>
Have you geared the NMU towards helping the maintainer? As there might
be disagreement on the notion of whether the maintainer actually needs
help on not, the DELAYED queue exists to give time to the maintainer to
react and has the beneficial side-effect of allowing for independent
reviews of the NMU diff.
</para>
</listitem>
<listitem>
<para>
Does your NMU really fix bugs? ("Bugs" means any kind of bugs, e.g.
wishlist bugs for packaging a new upstream version, but care should be
taken to minimize the impact to the maintainer.) Fixing cosmetic issues
or changing the packaging style (e.g. switching from cdbs to dh) in NMUs
is discouraged.
</para>
</listitem>
<listitem>
<para>
Did you give enough time to the maintainer? When was the bug reported to the
BTS? Being busy for a week or two isn't unusual.  Is the bug so severe that it
needs to be fixed right now, or can it wait a few more days?
</para>
</listitem>
<listitem>
<para>
How confident are you about your changes? Please remember the Hippocratic Oath:
"Above all, do no harm." It is better to leave a package with an open grave bug
than applying a non-functional patch, or one that hides the bug instead of
resolving it. If you are not 100% sure of what you did, it might be a good idea
to seek advice from others. Remember that if you break something in your NMU,
many people will be very unhappy about it.
</para>
</listitem>
<listitem>
<para>
Have you clearly expressed your intention to NMU, at least in the BTS?
It is also a good idea to try to contact the
maintainer by other means (private email, IRC).
</para>
</listitem>
<listitem>
<para>
If the maintainer is usually active and responsive, have you tried to contact
them? In general it should be considered preferable that maintainers take care
of an issue themselves and that they are given the chance to review and
correct your patch, because they can be expected to be more aware of potential
issues which an NMUer might miss. It is often a better use of everyone's time
if the maintainer is given an opportunity to upload a fix on their own.
</para>
</listitem>
</itemizedlist>
<para>
When doing an NMU, you must first make sure that your intention to NMU is
clear.  Then, you must send a patch with the differences between the
current package and your proposed NMU to the BTS. The
<command>nmudiff</command> script in the <systemitem role="package">devscripts</systemitem> package
might be helpful.
</para>
<para>
While preparing the patch, you should better be aware of any package-specific
practices that the maintainer might be using. Taking them into account
reduces the burden of integrating your changes into the normal package
workflow and thus increases the chances that integration will happen. A good
place where to look for for possible package-specific practices is
<ulink url="&url-debian-policy;ch-source.html#s-readmesource"><filename>debian/README.source</filename></ulink>.
</para>
<para>
Unless you have an excellent reason not to do so, you must then give some time
to the maintainer to react (for example, by uploading to the
<literal>DELAYED</literal> queue).  Here are some recommended values to use for delays:
</para>
<itemizedlist>
<listitem>
<para>
Upload fixing only release-critical bugs older than 7 days, with no maintainer activity on the bug for 7 days and no indication that a fix is in progress: 0 days
</para>
</listitem>
<listitem>
<para>
Upload fixing only release-critical bugs older than 7 days: 2 days
</para>
</listitem>
<listitem>
<para>
Upload fixing only release-critical and important bugs: 5 days
</para>
</listitem>
<listitem>
<para>
Other NMUs: 10 days
</para>
</listitem>
</itemizedlist>

<para>
Those delays are only examples. In some cases, such as uploads fixing security
issues, or fixes for trivial bugs that block a transition, it is desirable
that the fixed package reaches <literal>unstable</literal> sooner.
</para>

<para>
Sometimes, release managers decide to allow NMUs with shorter delays for a
subset of bugs (e.g release-critical bugs older than 7 days). Also, some
maintainers list themselves in the <ulink url="&url-low-threshold-nmu;">Low
Threshold NMU list</ulink>, and accept that NMUs are uploaded without delay. But
even in those cases, it's still a good idea to give the maintainer a few days
to react before you upload, especially if the patch wasn't available in the BTS
before, or if you know that the maintainer is generally active.
</para>

<para>
After you upload an NMU, you are responsible for the possible problems that you
might have introduced. You must keep an eye on the package (subscribing to the
package on the PTS is a good way to achieve this).
</para>

<para>
This is not a license to perform NMUs thoughtlessly.  If you NMU when it is
clear that the maintainers are active and would have acknowledged a patch in a
timely manner, or if you ignore the recommendations of this document, your
upload might be a cause of conflict with the maintainer.
You should always be prepared to
defend the wisdom of any NMU you perform on its own merits.
</para>
</section>

<section id="nmu-changelog">
<title>NMUs and <filename>debian/changelog</filename></title>
<para>
Just like any other (source) upload, NMUs must add an entry to
<filename>debian/changelog</filename>, telling what has changed with this
upload.  The first line of this entry must explicitely mention that this upload is an NMU, e.g.:
</para>
<screen>
  * Non-maintainer upload.
</screen>

<para>
The way to version NMUs differs for native and non-native packages.
</para>
<para>
If the package is a native package (without a Debian revision in the version number),
the version must be the version of the last maintainer upload, plus
<literal>+nmu<replaceable>X</replaceable></literal>, where
<replaceable>X</replaceable> is a counter starting at <literal>1</literal>.
If
the last upload was also an NMU, the counter should be increased.  For example,
if the current version is <literal>1.5</literal>, then an NMU would get
version <literal>1.5+nmu1</literal>.
</para>
<para>
If the package is not a native package, you should add a minor version number
to the Debian revision part of the version number (the portion after the last
hyphen). This extra number must start at <literal>1</literal>.  For example,
if the current version is <literal>1.5-2</literal>, then an NMU would get
version <literal>1.5-2.1</literal>. If a new upstream version
is packaged in the NMU, the Debian revision is set to <literal>0</literal>, for
example <literal>1.6-0.1</literal>.
</para>
<para>
In both cases, if the last upload was also an NMU, the counter should
be increased. For example, if the current version is
<literal>1.5+nmu3</literal> (a native package which has already been
NMUed), the NMU would get version <literal>1.5+nmu4</literal>.
</para>
<para>
A special versioning scheme is needed to avoid disrupting the maintainer's
work, since using an integer for the Debian revision will potentially
conflict with a maintainer upload already in preparation at the time of an
NMU, or even one sitting in the ftp NEW queue.
It also has the
benefit of making it visually clear that a package in the archive was not made
by the official maintainer.
</para>
<para>
If you upload a package to testing or stable, you sometimes need to "fork" the
version number tree. This is the case for security uploads, for example.  For
this, a version of the form
<literal>+deb<replaceable>X</replaceable>u<replaceable>Y</replaceable></literal>
should be used, where <replaceable>X</replaceable> is the major release number,
and <replaceable>Y</replaceable> is a counter starting at <literal>1</literal>.
For example, while Wheezy (Debian 7.0) is stable, a security NMU to stable for
a package at version <literal>1.5-3</literal> would have version
<literal>1.5-3+deb7u1</literal>, whereas a security NMU to Jessie would get
version <literal>1.5-3+deb8u1</literal>.
</para>
</section>

<section id="nmu-delayed">
<title>Using the <literal>DELAYED/</literal> queue</title>

<para>
Having to wait for a response after you request permission to NMU is
inefficient, because it costs the NMUer a context switch to come back to the
issue.
The <literal>DELAYED</literal> queue (see <xref linkend="delayed-incoming"/>)
allows the developer doing the NMU to perform all the necessary tasks at the
same time. For instance, instead of telling the maintainer that you will
upload the updated
package in 7 days, you should upload the package to
<literal>DELAYED/7</literal> and tell the maintainer that they have 7 days to
react.  During this time, the maintainer can ask you to delay the upload some
more, or cancel your upload.
</para>

<para>
The <literal>DELAYED</literal> queue should not be used to put additional
pressure on the maintainer. In particular, it's important that you are
available to cancel or delay the upload before the delay expires since the
maintainer cannot cancel the upload themselves.
</para>

<para>
If you make an NMU to <literal>DELAYED</literal> and the maintainer updates
the package before the delay expires, your upload will be rejected because a
newer version is already available in the archive.
Ideally, the maintainer will take care to include your proposed changes (or
at least a solution for the problems they address) in that upload.
</para>

</section>

<section id="nmu-maintainer">
<title>NMUs from the maintainer's point of view</title>

<para>
When someone NMUs your package, this means they want to help you to keep it in
good shape.  This gives users fixed packages faster.  You
can consider asking the NMUer to become a co-maintainer of the package.
Receiving an NMU on a package is not a bad
thing; it just means that the package is interesting enough for other people to
work on it.
</para>

<para>
To acknowledge an NMU, include its changes and changelog entry in your next
maintainer upload.  If you do not acknowledge the NMU by including the
NMU changelog entry in your changelog, the bugs will remain closed in the
BTS but will be listed as affecting your maintainer version of the package.
</para>

</section>

<section id="nmu-binnmu">
<title>Source NMUs vs Binary-only NMUs (binNMUs)</title>

<para>
The full name of an NMU is <emphasis>source NMU</emphasis>.  There is also
another type, namely the <emphasis>binary-only NMU</emphasis>, or
<emphasis>binNMU</emphasis>.  A binNMU is also a package upload by someone
other than the package's maintainer.  However, it is a binary-only upload.
</para>

<para>
When a library (or other dependency) is updated, the packages using it may need
to be rebuilt.  Since no changes to the source are needed, the same source
package is used.
</para>

<para>
BinNMUs are usually triggered on the buildds by wanna-build.
An entry is added to <filename>debian/changelog</filename>,
explaining why the upload was needed and increasing the version number as
described in <xref linkend="binary-only-nmu"/>.
This entry should not be included in the next upload.
</para>

<para>
Buildds upload packages for their architecture to the archive as binary-only
uploads.  Strictly speaking, these are binNMUs.  However, they are not normally
called NMU, and they don't add an entry to <filename>debian/changelog</filename>.
</para>

</section>

<section id="nmu-qa-upload">
<title>NMUs vs QA uploads</title>

<para>
NMUs are uploads of packages by somebody else than their assigned maintainer.
There is
another type of upload where the uploaded package is not yours: QA uploads. QA
uploads are uploads of orphaned packages.
</para>

<para>
QA uploads are very much like normal maintainer uploads: they may fix anything,
even minor issues; the version numbering is normal, and there is no need to use
a delayed upload.  The difference is that you are not listed as the <literal>Maintainer</literal>
or <literal>Uploader</literal> for the package.  Also, the changelog entry of a QA upload has a
special first line:
</para>

<screen>
 * QA upload.
</screen>

<para>
If you want to do an NMU, and it seems that the maintainer is not active, it is
wise to check if the package is orphaned
(this information is displayed on the package's Package Tracking System page).
When doing the first QA upload to an
orphaned package, the maintainer should be set to <literal>Debian QA Group
&lt;packages@qa.debian.org&gt;</literal>.  Orphaned packages which did
not yet have a QA upload still have their old maintainer set.  There is a list
of them at <ulink url="&url-orphaned-not-qa;"/>.
</para>

<para>
Instead of doing a QA upload, you can also consider adopting the package by
making yourself the maintainer.  You don't need permission from anybody to
adopt an orphaned package, you can just set yourself as maintainer and upload
the new version (see <xref linkend="adopting"/>).
</para>

</section>

<section id="nmu-team-upload">
<title>NMUs vs team uploads</title>

<para>
Sometimes you are fixing and/or updating a package because you are member of a
packaging team (which uses a mailing list as <literal>Maintainer</literal> or <literal>Uploader</literal>, see <xref
linkend="collaborative-maint"/>) but you don't want to add yourself to <literal>Uploaders</literal>
because you do not plan to contribute regularly to this specific package. If it
conforms with your team's policy, you can perform a normal upload without
being listed directly as <literal>Maintainer</literal> or <literal>Uploader</literal>. In that case, you should
start your changelog entry with the following line:
</para>

<screen>
 * Team upload.
</screen>

</section>

</section>

<section id="collaborative-maint">
<title>Collaborative maintenance</title>
<para>
Collaborative maintenance is a term describing the sharing of Debian package
maintenance duties by several people.  This collaboration is almost always a
good idea, since it generally results in higher quality and faster bug fix
turnaround times.  It is strongly recommended that packages with a priority of
<literal>standard</literal> or which are part of the base set have
co-maintainers.
</para>
<para>
Generally there is a primary maintainer and one or more co-maintainers.  The
primary maintainer is the person whose name is listed in the
<literal>Maintainer</literal> field of the <filename>debian/control</filename>
file.  Co-maintainers are all the other maintainers,
usually listed in the <literal>Uploaders</literal> field of the
<filename>debian/control</filename> file.
</para>
<para>
In its most basic form, the process of adding a new co-maintainer is quite
easy:
</para>
<itemizedlist>
<listitem>
<para>
Setup the co-maintainer with access to the sources you build the package from.
Generally this implies you are using a network-capable version control system,
such as <literal>CVS</literal> or <literal>Subversion</literal>.  Alioth (see
<xref linkend="alioth"/>) provides such tools, amongst others.
</para>
</listitem>
<listitem>
<para>
Add the co-maintainer's correct maintainer name and address to the
<literal>Uploaders</literal> field in the first paragraph of the
<filename>debian/control</filename> file.
</para>
<screen>
Uploaders: John Buzz &lt;jbuzz@debian.org&gt;, Adam Rex &lt;arex@debian.org&gt;
</screen>
</listitem>
<listitem>
<para>
Using the PTS (<xref linkend="pkg-tracking-system"/>), the co-maintainers
should subscribe themselves to the appropriate source package.
</para>
</listitem>
</itemizedlist>
<para>
Another form of collaborative maintenance is team maintenance, which is
recommended if you maintain several packages with the same group of developers.
In that case, the <literal>Maintainer</literal> and <literal>Uploaders</literal> field of each package must be
managed with care.  It is recommended to choose between one of the two
following schemes:
</para>
<orderedlist numeration="arabic">
<listitem>
<para>
Put the team member mainly responsible for the package in the <literal>Maintainer</literal> field.
In the <literal>Uploaders</literal>, put the mailing list address, and the team members who care
for the package.
</para>
</listitem>
<listitem>
<para>
Put the mailing list address in the <literal>Maintainer</literal> field.  In the <literal>Uploaders</literal> field,
put the team members who care for the package.  In this case, you must make
sure the mailing list accept bug reports without any human interaction (like
moderation for non-subscribers).
</para>
</listitem>
</orderedlist>

<para>
In any case, it is a bad idea to automatically put all team members in the
<literal>Uploaders</literal> field. It clutters the Developer's Package Overview listing (see
<xref linkend="ddpo"/>) with packages one doesn't really care for, and creates
a false sense of good maintenance. For the same reason, team members do
not need to add themselves to the <literal>Uploaders</literal> field just because they are
uploading the package once, they can do a “Team upload” (see <xref
linkend="nmu-team-upload"/>). Conversely, it is a bad idea to keep a
package with only the mailing list address as a <literal>Maintainer</literal> and no
<literal>Uploaders</literal>.
</para>
</section>

<section id="testing">
<title>The testing distribution</title>
<section id="testing-basics">
<title>Basics</title>
<para>
Packages are usually installed into the <literal>testing</literal> distribution
after they have undergone some degree of <literal>testing</literal> in
<literal>unstable</literal>.
</para>
<para>
They must be in sync on all architectures and mustn't have dependencies that
make them uninstallable; they also have to have generally no known
release-critical bugs at the time they're installed into <literal>testing</literal>.
This way, <literal>testing</literal> should always be close to
being a release candidate.  Please see below for details.
</para>
</section>

<section id="testing-unstable">
<title>Updates from unstable</title>
<para>
The scripts that update the <literal>testing</literal> distribution are run
twice each day, right after the installation of the updated packages; these
scripts are called <literal>britney</literal>.  They generate the
<filename>Packages</filename> files for the <literal>testing</literal>
distribution, but they do so in an intelligent manner; they try to avoid any
inconsistency and to use only non-buggy packages.
</para>
<para>
The inclusion of a package from <literal>unstable</literal> is conditional on
the following:
</para>
<itemizedlist>
<listitem>
<para>
The package must have been available in <literal>unstable</literal> for 2, 5
or 10 days, depending on the urgency (high, medium or low).  Please note that
the urgency is sticky, meaning that the highest urgency uploaded since the
previous <literal>testing</literal> transition is taken into account;
</para>
</listitem>
<listitem>
<para>
It must not have new release-critical bugs (RC bugs affecting the version
available in <literal>unstable</literal>, but not affecting the version in
<literal>testing</literal>);
</para>
</listitem>
<listitem>
<para>
It must be available on all architectures on which it has previously been built
in <literal>unstable</literal>. <link linkend="dak-ls">dak ls</link> may be of interest
to check that information;
</para>
</listitem>
<listitem>
<para>
It must not break any dependency of a package which is already available in
<literal>testing</literal>;
</para>
</listitem>
<listitem>
<para>
The packages on which it depends must either be available in
<literal>testing</literal> or they must be accepted into
<literal>testing</literal> at the same time (and they will be if they fulfill
all the necessary criteria);
</para>
</listitem>
<listitem>
<para>
The phase of the project.  I.e. automatic transitions are turned off during
the <emphasis>freeze</emphasis> of the <literal>testing</literal> distribution.
</para>
</listitem>
</itemizedlist>
<para>
To find out whether a package is progressing into <literal>testing</literal>
or not, see the <literal>testing</literal> script output on the <ulink
url="&url-testing-maint;">web page of the testing
distribution</ulink>, or use the program <command>grep-excuses</command> which
is in the <systemitem role="package">devscripts</systemitem> package.  This
utility can easily be used in a <citerefentry>
<refentrytitle>crontab</refentrytitle> <manvolnum>5</manvolnum> </citerefentry>
to keep yourself informed of the progression of your packages into
<literal>testing</literal>.
</para>
<para>
The <filename>update_excuses</filename> file does not always give the precise
reason why the package is refused; you may have to find it on your own by
looking for what would break with the inclusion of the package.  The <ulink
url="&url-testing-maint;">testing web page</ulink> gives some
more information about the usual problems which may be causing such troubles.
</para>
<para>
Sometimes, some packages never enter <literal>testing</literal> because the
set of interrelationship is too complicated and cannot be sorted out by the
scripts.  See below for details.
</para>
<para>
Some further dependency analysis is shown on <ulink
url="https://release.debian.org/migration/"></ulink> — but be warned, this page also
shows build dependencies which are not considered by britney.
</para>
<section id="outdated">
<title>Out-of-date</title>
<para>
<!-- FIXME: better rename this file than document rampant professionalism? -->
For the <literal>testing</literal> migration script, outdated means: There are
different versions in <literal>unstable</literal> for the release architectures
(except for the architectures in fuckedarches; fuckedarches is a list of
architectures that don't keep up (in <filename>update_out.py</filename>), but
currently, it's empty).  outdated has nothing whatsoever to do with the
architectures this package has in <literal>testing</literal>.
</para>
<para>
Consider this example:
</para>
<informaltable pgwide="1">
<tgroup cols="3">
<thead>
<row>
<entry></entry>
<entry>alpha</entry>
<entry>arm</entry>
</row>
</thead>
<tbody>
<row>
<entry>testing</entry>
<entry>1</entry>
<entry>-</entry>
</row>
<row>
<entry>unstable</entry>
<entry>1</entry>
<entry>2</entry>
</row>
</tbody>
</tgroup>
</informaltable>
<para>
The package is out of date on <literal>alpha</literal> in <literal>unstable</literal>, and will
not go to <literal>testing</literal>. Removing the package would not help at all, the
package is still out of date on <literal>alpha</literal>, and will not
propagate to <literal>testing</literal>.
</para>
<para>
However, if ftp-master removes a package in <literal>unstable</literal> (here
on <literal>arm</literal>):
</para>
<informaltable pgwide="1">
<tgroup cols="4">
<thead>
<row>
<entry></entry>
<entry>alpha</entry>
<entry>arm</entry>
<entry>hurd-i386</entry>
</row>
</thead>
<tbody>
<row>
<entry>testing</entry>
<entry>1</entry>
<entry>1</entry>
<entry>-</entry>
</row>
<row>
<entry>unstable</entry>
<entry>2</entry>
<entry>-</entry>
<entry>1</entry>
</row>
</tbody>
</tgroup>
</informaltable>
<para>
In this case, the package is up to date on all release architectures in
<literal>unstable</literal> (and the extra <literal>hurd-i386</literal>
doesn't matter, as it's not a release architecture).
</para>
<para>
Sometimes, the question is raised if it is possible to allow packages in that
are not yet built on all architectures: No.  Just plainly no.  (Except if you
maintain glibc or so.)
</para>
</section>

<section id="removals">
<title>Removals from testing</title>
<para>
Sometimes, a package is removed to allow another package in: This happens only
to allow <emphasis>another</emphasis> package to go in if it's ready in every
other sense.  Suppose e.g.  that <literal>a</literal> cannot be installed
with the new version of <literal>b</literal>; then <literal>a</literal> may
be removed to allow <literal>b</literal> in.
</para>
<para>
Of course, there is another reason to remove a package from <literal>testing</literal>:
It's just too buggy (and having a single RC-bug is enough to be
in this state).
</para>
<para>
Furthermore, if a package has been removed from <literal>unstable</literal>,
and no package in <literal>testing</literal> depends on it any more, then it
will automatically be removed.
</para>
</section>

<section id="circular">
<title>Circular dependencies</title>
<para>
A situation which is not handled very well by britney is if package
<literal>a</literal> depends on the new version of package
<literal>b</literal>, and vice versa.
</para>
<para>
An example of this is:
</para>
<informaltable pgwide="1">
<tgroup cols="3">
<thead>
<row>
<entry></entry>
<entry>testing</entry>
<entry>unstable</entry>
</row>
</thead>
<tbody>
<row>
<entry>a</entry>
<entry>1; depends: b=1</entry>
<entry>2; depends: b=2</entry>
</row>
<row>
<entry>b</entry>
<entry>1; depends: a=1</entry>
<entry>2; depends: a=2</entry>
</row>
</tbody>
</tgroup>
</informaltable>
<para>
Neither package <literal>a</literal> nor package <literal>b</literal> is
considered for update.
</para>
<para>
Currently, this requires some manual hinting from the release team.  Please
contact them by sending mail to &email-debian-release; if this
happens to one of your packages.
</para>
</section>

<section id="s5.13.2.4">
<title>Influence of package in testing</title>
<para>
Generally, there is nothing that the status of a package in <literal>testing</literal>
means for transition of the next version from <literal>unstable</literal>
to <literal>testing</literal>, with two exceptions:
If the RC-bugginess of the package goes down, it may go in even if it is still
RC-buggy.  The second exception is if the version of the package in
<literal>testing</literal> is out of sync on the different arches: Then any arch might
just upgrade to the version of the source package; however, this can happen
only if the package was previously forced through, the arch is in fuckedarches,
or there was no binary package of that arch present in <literal>unstable</literal>
at all during the <literal>testing</literal> migration.
</para>
<para>
In summary this means: The only influence that a package being in
<literal>testing</literal> has on a new version of the same package is that the new
version might go in easier.
</para>
</section>

<section id="details">
<title>Details</title>
<para>
If you are interested in details, this is how britney works:
</para>
<para>
The packages are looked at to determine whether they are valid candidates.
This gives the update excuses.  The most common reasons why a package is not
considered are too young, RC-bugginess, and out of date on some arches.  For
this part of britney, the release managers have hammers of various sizes,
called hints (see below), to force britney to consider a package.
</para>
<para>
Now, the more complex part happens: Britney tries to update <literal>testing</literal>
with the valid candidates. For that, britney tries to add each
valid candidate to the testing distribution. If the number of uninstallable
packages in <literal>testing</literal> doesn't increase, the package is
accepted. From that point on, the accepted package is considered to be part
of <literal>testing</literal>, such that all subsequent installability
tests include this package.  Hints from the release team are processed
before or after this main run, depending on the exact type.
</para>
<para>
If you want to see more details, you can look it up on <ulink
url="https://&ftp-master-host;/testing/update_output/"></ulink>.
</para>
<para>
The hints are available via <ulink
url="https://&ftp-master-host;/testing/hints/"></ulink>, where you can find
the
<ulink url="https://&ftp-master-host;/testing/hints/README">description</ulink>
as well.  With the hints, the Debian Release team can block or unblock
packages, ease or force packages into <literal>testing</literal>, remove
packages from <literal>testing</literal>, approve uploads to
<link linkend="t-p-u">testing-proposed-updates</link> or override the urgency.
</para>
</section>

</section>

<section id="t-p-u">
<title>Direct updates to testing</title>
<para>
The <literal>testing</literal> distribution is fed with packages from
<literal>unstable</literal> according to the rules explained above.  However,
in some cases, it is necessary to upload packages built only for
<literal>testing</literal>.  For that, you may want to upload to
<literal>testing-proposed-updates</literal>.
</para>
<para>
Keep in mind that packages uploaded there are not automatically processed, they
have to go through the hands of the release manager.  So you'd better have a
good reason to upload there.  In order to know what a good reason is in the
release managers' eyes, you should read the instructions that they regularly
give on &email-debian-devel-announce;.
</para>
<para>
You should not upload to <literal>testing-proposed-updates</literal> when you
can update your packages through <literal>unstable</literal>.  If you can't
(for example because you have a newer development version in <literal>unstable</literal>),
you may use this facility, but it is recommended that you ask for
authorization from the release manager first.  Even if a package is frozen,
updates through <literal>unstable</literal> are possible, if the upload via
<literal>unstable</literal> does not pull in any new dependencies.
</para>
<para>
Version numbers are usually selected by adding the codename of the
<literal>testing</literal> distribution and a running number, like
<literal>1.2squeeze1</literal> for the first upload through
<literal>testing-proposed-updates</literal> of package version
<literal>1.2</literal>.
</para>
<para>
Please make sure you didn't miss any of these items in your upload:
</para>
<itemizedlist>
<listitem>
<para>
Make sure that your package really needs to go through
<literal>testing-proposed-updates</literal>, and can't go through
<literal>unstable</literal>;
</para>
</listitem>
<listitem>
<para>
Make sure that you included only the minimal amount of changes;
</para>
</listitem>
<listitem>
<para>
Make sure that you included an appropriate explanation in the changelog;
</para>
</listitem>
<listitem>
<para>
Make sure that you've written <literal>testing</literal> or
<literal>testing-proposed-updates</literal> into your target distribution;
</para>
</listitem>
<listitem>
<para>
Make sure that you've built and tested your package in
<literal>testing</literal>, not in <literal>unstable</literal>;
</para>
</listitem>
<listitem>
<para>
Make sure that your version number is higher than the version in
<literal>testing</literal> and <literal>testing-proposed-updates</literal>,
and lower than in <literal>unstable</literal>;
</para>
</listitem>
<listitem>
<para>
After uploading and successful build on all platforms, contact the release team
at &email-debian-release; and ask them to approve your upload.
</para>
</listitem>
</itemizedlist>
</section>

<section id="faq">
<title>Frequently asked questions</title>
<section id="rc">
<title>What are release-critical bugs, and how do they get counted?</title>
<para>
All bugs of some higher severities are by default considered release-critical;
currently, these are <literal>critical</literal>, <literal>grave</literal> and
<literal>serious</literal> bugs.
</para>
<para>
Such bugs are presumed to have an impact on the chances that the package will
be released with the <literal>stable</literal> release of Debian: in general,
if a package has open release-critical bugs filed on it, it won't get into
<literal>testing</literal>, and consequently won't be released in
<literal>stable</literal>.
</para>
<para>
The <literal>unstable</literal> bug count are all release-critical bugs which
are marked to apply to <replaceable>package</replaceable>/<replaceable>version</replaceable>
combinations that are available in unstable for a release
architecture. The <literal>testing</literal> bug count is defined analogously.
</para>
</section>

<section id="s5.13.4.2">
<title>How could installing a package into <literal>testing</literal> possibly
break other packages?</title>
<para>
The structure of the distribution archives is such that they can only contain
one version of a package; a package is defined by its name.  So when the source
package <literal>acmefoo</literal> is installed into <literal>testing</literal>,
along with its binary packages <literal>acme-foo-bin</literal>,
<literal>acme-bar-bin</literal>, <literal>libacme-foo1</literal> and
<literal>libacme-foo-dev</literal>, the old version is removed.
</para>
<para>
However, the old version may have provided a binary package with an old soname
of a library, such as <literal>libacme-foo0</literal>.  Removing the old
<literal>acmefoo</literal> will remove <literal>libacme-foo0</literal>, which
will break any packages which depend on it.
</para>
<para>
Evidently, this mainly affects packages which provide changing sets of binary
packages in different versions (in turn, mainly libraries).  However, it will
also affect packages upon which versioned dependencies have been declared of
the ==, &lt;=, or &lt;&lt; varieties.
</para>
<para>
When the set of binary packages provided by a source package change in this
way, all the packages that depended on the old binaries will have to be updated
to depend on the new binaries instead.  Because installing such a source
package into <literal>testing</literal> breaks all the packages that depended on
it in <literal>testing</literal>,
some care has to be taken now: all the depending packages must be updated and
ready to be installed themselves so that they won't be broken, and, once
everything is ready, manual intervention by the release manager or an assistant
is normally required.
</para>
<para>
If you are having problems with complicated groups of packages like this,
contact &email-debian-devel; or &email-debian-release; for help.
</para>
</section>

</section>

</section>

</chapter>