doc/apt-ftparchive.1.xml

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   5 <!ENTITY % aptent SYSTEM "apt.ent">
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  10 <refentry>
  11
  12  <refentryinfo>
  13    &apt-author.jgunthorpe;
  14    &apt-author.team;
  15    &apt-email;
  16    &apt-product;
  17    <!-- The last update date -->
  18    <date>17 August 2009</date>
  19  </refentryinfo>
  20
  21  <refmeta>
  22    <refentrytitle>apt-ftparchive</refentrytitle>
  23    <manvolnum>1</manvolnum>
  24    <refmiscinfo class="manual">APT</refmiscinfo>
  25  </refmeta>
  26
  27  <!-- Man page title -->
  28  <refnamediv>
  29     <refname>apt-ftparchive</refname>
  30     <refpurpose>Utility to generate index files</refpurpose>
  31  </refnamediv>
  32
  33  <!-- Arguments -->
  34  <refsynopsisdiv>
  35    <cmdsynopsis>
  36       <command>apt-ftparchive</command>
  37       <arg><option>-hvdsq</option></arg>
  38       <arg><option>--md5</option></arg>
  39       <arg><option>--delink</option></arg>
  40       <arg><option>--readonly</option></arg>
  41       <arg><option>--contents</option></arg>
  42       <arg><option>--arch <replaceable>architecture</replaceable></option></arg>
  43       <arg><option>-o <replaceable>config</replaceable>=<replaceable>string</replaceable></option></arg>
  44       <arg><option>-c=<replaceable>file</replaceable></option></arg>
  45       <group choice="req">
  46          <arg>packages<arg choice="plain" rep="repeat"><replaceable>path</replaceable></arg><arg><replaceable>override</replaceable><arg><replaceable>pathprefix</replaceable></arg></arg></arg>
  47          <arg>sources<arg choice="plain" rep="repeat"><replaceable>path</replaceable></arg><arg><replaceable>override</replaceable><arg><replaceable>pathprefix</replaceable></arg></arg></arg>
  48          <arg>contents <arg choice="plain"><replaceable>path</replaceable></arg></arg>
  49          <arg>release <arg choice="plain"><replaceable>path</replaceable></arg></arg>
  50          <arg>generate <arg choice="plain"><replaceable>config-file</replaceable></arg> <arg choice="plain" rep="repeat"><replaceable>section</replaceable></arg></arg>
  51          <arg>clean <arg choice="plain"><replaceable>config-file</replaceable></arg></arg>
  52       </group>
  53    </cmdsynopsis>
  54  </refsynopsisdiv>
  55
  56  <refsect1><title>Description</title>
  57    <para><command>apt-ftparchive</command> is the command line tool that generates the index
  58    files that APT uses to access a distribution source. The index files should
  59    be generated on the origin site based on the content of that site.</para>
  60
  61    <para><command>apt-ftparchive</command> is a superset of the &dpkg-scanpackages; program,
  62    incorporating its entire functionality via the <literal>packages</literal> command.
  63    It also contains a contents file generator, <literal>contents</literal>, and an
  64    elaborate means to 'script' the generation process for a complete
  65    archive.</para>
  66
  67    <para>Internally <command>apt-ftparchive</command> can make use of binary databases to
  68    cache the contents of a .deb file and it does not rely on any external
  69    programs aside from &gzip;. When doing a full generate it automatically
  70    performs file-change checks and builds the desired compressed output files.</para>
  71
  72    <para>Unless the <option>-h</option>, or <option>--help</option> option is given one of the
  73    commands below must be present.</para>
  74
  75    <variablelist>
  76      <varlistentry><term>packages</term>
  77      <listitem><para>
  78      The packages command generates a package file from a directory tree. It
  79      takes the given directory and recursively searches it for .deb files,
  80      emitting a package record to stdout for each. This command is
  81      approximately equivalent to &dpkg-scanpackages;.</para>
  82
  83      <para>The option <option>--db</option> can be used to specify a binary caching DB.</para></listitem>
  84      </varlistentry>
  85
  86      <varlistentry><term>sources</term>
  87      <listitem><para>
  88      The <literal>sources</literal> command generates a source index file from a directory tree.
  89      It takes the given directory and recursively searches it for .dsc files,
  90      emitting a source record to stdout for each. This command is approximately
  91      equivalent to &dpkg-scansources;.</para>
  92      <para>
  93      If an override file is specified then a source override file will be
  94      looked for with an extension of .src. The --source-override option can be
  95      used to change the source override file that will be used.</para></listitem>
  96      </varlistentry>
  97
  98      <varlistentry><term>contents</term>
  99      <listitem><para>
 100      The <literal>contents</literal> command generates a contents file from a directory tree. It
 101      takes the given directory and recursively searches it for .deb files,
 102      and reads the file list from each file. It then sorts and writes to stdout
 103      the list of files matched to packages. Directories are not written to
 104      the output. If multiple packages own the same file then each package is
 105      separated by a comma in the output.</para>
 106      <para>
 107      The option <option>--db</option> can be used to specify a binary caching DB.</para></listitem>
 108      </varlistentry>
 109
 110      <varlistentry><term>release</term>
 111      <listitem><para>
 112      The <literal>release</literal> command generates a Release file from a
 113      directory tree. It recursively searches the given directory for
 114      Packages, Packages.gz, Packages.bz2, Sources, Sources.gz,
 115      Sources.bz2, Release and md5sum.txt files.  It then writes to
 116      stdout a Release file containing an MD5 digest and SHA1 digest
 117      for each file.</para>
 118      <para>
 119      Values for the additional metadata fields in the Release file are
 120      taken from the corresponding variables under
 121      <literal>APT::FTPArchive::Release</literal>,
 122      e.g. <literal>APT::FTPArchive::Release::Origin</literal>.  The supported fields
 123      are: <literal>Origin</literal>, <literal>Label</literal>, <literal>Suite</literal>,
 124      <literal>Version</literal>, <literal>Codename</literal>, <literal>Date</literal>,
 125      <literal>Valid-Until</literal>, <literal>Architectures</literal>,
 126      <literal>Components</literal>, <literal>Description</literal>.</para></listitem>
 127
 128      </varlistentry>
 129
 130      <varlistentry><term>generate</term>
 131      <listitem><para>
 132      The <literal>generate</literal> command is designed to be runnable from a cron script and
 133      builds indexes according to the given config file. The config language
 134      provides a flexible means of specifying which index files are built from
 135      which directories, as well as providing a simple means of maintaining the
 136      required settings.</para></listitem>
 137      </varlistentry>
 138
 139      <varlistentry><term>clean</term>
 140      <listitem><para>
 141      The <literal>clean</literal> command tidies the databases used by the given
 142      configuration file by removing any records that are no longer necessary.</para></listitem>
 143      </varlistentry>
 144    </variablelist>
 145  </refsect1>
 146
 147  <refsect1><title>The Generate Configuration</title>
 148    <para>
 149    The <literal>generate</literal> command uses a configuration file to describe the
 150    archives that are going to be generated. It follows the typical ISC
 151    configuration format as seen in ISC tools like bind 8 and dhcpd.
 152    &apt-conf; contains a description of the syntax. Note that the generate
 153    configuration is parsed in sectional manner, but &apt-conf; is parsed in a
 154    tree manner. This only effects how the scope tag is handled.</para>
 155
 156    <para>
 157    The generate configuration has 4 separate sections, each described below.</para>
 158
 159    <refsect2><title>Dir Section</title>
 160      <para>
 161      The <literal>Dir</literal> section defines the standard directories needed to
 162      locate the files required during the generation process. These
 163      directories are prepended certain relative paths defined in later
 164      sections to produce a complete an absolute path.</para>
 165      <variablelist>
 166       <varlistentry><term>ArchiveDir</term>
 167       <listitem><para>
 168       Specifies the root of the FTP archive, in a standard
 169       Debian configuration this is the directory that contains the
 170       <filename>ls-LR</filename> and dist nodes.</para></listitem>
 171       </varlistentry>
 172
 173       <varlistentry><term>OverrideDir</term>
 174       <listitem><para>
 175       Specifies the location of the override files.</para></listitem>
 176       </varlistentry>
 177
 178       <varlistentry><term>CacheDir</term>
 179       <listitem><para>
 180       Specifies the location of the cache files</para></listitem>
 181       </varlistentry>
 182
 183       <varlistentry><term>FileListDir</term>
 184       <listitem><para>
 185       Specifies the location of the file list files,
 186       if the <literal>FileList</literal> setting is used below.</para></listitem>
 187       </varlistentry>
 188      </variablelist>
 189    </refsect2>
 190
 191    <refsect2><title>Default Section</title>
 192      <para>
 193      The <literal>Default</literal> section specifies default values, and settings
 194      that control the operation of the generator. Other sections may override
 195      these defaults with a per-section setting.</para>
 196      <variablelist>
 197       <varlistentry><term>Packages::Compress</term>
 198       <listitem><para>
 199       Sets the default compression schemes to use
 200       for the Package index files. It is a string that contains a space
 201       separated list of at least one of: '.' (no compression), 'gzip' and
 202       'bzip2'. The default for all compression schemes is '. gzip'.</para></listitem>
 203       </varlistentry>
 204
 205       <varlistentry><term>Packages::Extensions</term>
 206       <listitem><para>
 207       Sets the default list of file extensions that are package files.
 208       This defaults to '.deb'.</para></listitem>
 209       </varlistentry>
 210
 211       <varlistentry><term>Sources::Compress</term>
 212       <listitem><para>
 213       This is similar to <literal>Packages::Compress</literal>
 214       except that it controls the compression for the Sources files.</para></listitem>
 215       </varlistentry>
 216
 217       <varlistentry><term>Sources::Extensions</term>
 218       <listitem><para>
 219       Sets the default list of file extensions that are source files.
 220       This defaults to '.dsc'.</para></listitem>
 221       </varlistentry>
 222
 223       <varlistentry><term>Contents::Compress</term>
 224       <listitem><para>
 225       This is similar to <literal>Packages::Compress</literal>
 226       except that it controls the compression for the Contents files.</para></listitem>
 227       </varlistentry>
 228
 229       <varlistentry><term>Translation::Compress</term>
 230       <listitem><para>
 231       This is similar to <literal>Packages::Compress</literal>
 232       except that it controls the compression for the Translation-en master file.</para></listitem>
 233       </varlistentry>
 234
 235       <varlistentry><term>DeLinkLimit</term>
 236       <listitem><para>
 237       Specifies the number of kilobytes to delink (and
 238       replace with hard links) per run. This is used in conjunction with the
 239       per-section <literal>External-Links</literal> setting.</para></listitem>
 240       </varlistentry>
 241
 242       <varlistentry><term>FileMode</term>
 243       <listitem><para>
 244       Specifies the mode of all created index files. It
 245       defaults to 0644. All index files are set to this mode with no regard
 246       to the umask.</para></listitem>
 247       </varlistentry>
 248
 249       <varlistentry><term>LongDescription</term>
 250       <listitem><para>
 251       Sets if long descriptions should be included in the Packages file or split
 252       out into a master Translation-en file.</para></listitem>
 253       </varlistentry>
 254      </variablelist>
 255    </refsect2>
 256
 257    <refsect2><title>TreeDefault Section</title>
 258      <para>
 259      Sets defaults specific to <literal>Tree</literal> sections. All of these
 260      variables are substitution variables and have the strings $(DIST),
 261      $(SECTION) and $(ARCH) replaced with their respective values.</para>
 262
 263      <variablelist>
 264       <varlistentry><term>MaxContentsChange</term>
 265       <listitem><para>
 266       Sets  the number of kilobytes of contents
 267       files that are generated each day. The contents files are round-robined
 268       so that over several days they will all be rebuilt.</para></listitem>
 269       </varlistentry>
 270
 271       <varlistentry><term>ContentsAge</term>
 272       <listitem><para>
 273       Controls the number of days a contents file is allowed
 274       to be checked without changing. If this limit is passed the mtime of the
 275       contents file is updated. This case can occur if the package file is
 276       changed in such a way that does not result in a new contents file
 277       [override edit for instance]. A hold off is allowed in hopes that new
 278       .debs will be installed, requiring a new file anyhow. The default is 10,
 279       the units are in days.</para></listitem>
 280       </varlistentry>
 281
 282       <varlistentry><term>Directory</term>
 283       <listitem><para>
 284       Sets the top of the .deb directory tree. Defaults to
 285       <filename>$(DIST)/$(SECTION)/binary-$(ARCH)/</filename></para></listitem>
 286       </varlistentry>
 287
 288       <varlistentry><term>SrcDirectory</term>
 289       <listitem><para>
 290       Sets the top of the source package directory tree. Defaults to
 291       <filename>$(DIST)/$(SECTION)/source/</filename></para></listitem>
 292       </varlistentry>
 293
 294       <varlistentry><term>Packages</term>
 295       <listitem><para>
 296       Sets the output Packages file. Defaults to
 297       <filename>$(DIST)/$(SECTION)/binary-$(ARCH)/Packages</filename></para></listitem>
 298       </varlistentry>
 299
 300       <varlistentry><term>Sources</term>
 301       <listitem><para>
 302       Sets the output Sources file. Defaults to
 303       <filename>$(DIST)/$(SECTION)/source/Sources</filename></para></listitem>
 304       </varlistentry>
 305
 306       <varlistentry><term>Translation</term>
 307       <listitem><para>
 308       Set the output Translation-en master file with the long descriptions if they
 309       should be not included in the Packages file. Defaults to
 310       <filename>$(DIST)/$(SECTION)/i18n/Translation-en</filename></para></listitem>
 311       </varlistentry>
 312
 313       <varlistentry><term>InternalPrefix</term>
 314       <listitem><para>
 315       Sets the path prefix that causes a symlink to be
 316       considered an internal link instead of an external link. Defaults to
 317       <filename>$(DIST)/$(SECTION)/</filename></para></listitem>
 318       </varlistentry>
 319
 320       <varlistentry><term>Contents</term>
 321       <listitem><para>
 322       Sets the output Contents file. Defaults to
 323       <filename>$(DIST)/Contents-$(ARCH)</filename>. If this setting causes multiple
 324       Packages files to map onto a single Contents file (such as the default)
 325       then <command>apt-ftparchive</command> will integrate those package files
 326       together automatically.</para></listitem>
 327       </varlistentry>
 328
 329       <varlistentry><term>Contents::Header</term>
 330       <listitem><para>
 331       Sets header file to prepend to the contents output.</para></listitem>
 332       </varlistentry>
 333
 334       <varlistentry><term>BinCacheDB</term>
 335       <listitem><para>
 336       Sets the binary cache database to use for this
 337       section. Multiple sections can share the same database.</para></listitem>
 338       </varlistentry>
 339
 340       <varlistentry><term>FileList</term>
 341       <listitem><para>
 342       Specifies that instead of walking the directory tree,
 343       <command>apt-ftparchive</command> should read the list of files from the given
 344       file. Relative files names are prefixed with the archive directory.</para></listitem>
 345       </varlistentry>
 346
 347       <varlistentry><term>SourceFileList</term>
 348       <listitem><para>
 349       Specifies that instead of walking the directory tree,
 350       <command>apt-ftparchive</command> should read the list of files from the given
 351       file. Relative files names are prefixed with the archive directory.
 352       This is used when processing source indexes.</para></listitem>
 353       </varlistentry>
 354      </variablelist>
 355    </refsect2>
 356
 357    <refsect2><title>Tree Section</title>
 358      <para>
 359      The <literal>Tree</literal> section defines a standard Debian file tree which
 360      consists of a base directory, then multiple sections in that base
 361      directory and finally multiple Architectures in each section. The exact
 362      pathing used is defined by the <literal>Directory</literal> substitution variable.</para>
 363      <para>
 364      The <literal>Tree</literal> section takes a scope tag which sets the
 365      <literal>$(DIST)</literal> variable and defines the root of the tree
 366      (the path is prefixed by <literal>ArchiveDir</literal>).
 367      Typically this is a setting such as <filename>dists/&stable-codename;</filename>.</para>
 368      <para>
 369      All of the settings defined in the <literal>TreeDefault</literal> section can be
 370      use in a <literal>Tree</literal> section as well as three new variables.</para>
 371      <para>
 372      When processing a <literal>Tree</literal> section <command>apt-ftparchive</command>
 373      performs an operation similar to:
 374      <programlisting>
 375 for i in Sections do
 376    for j in Architectures do
 377       Generate for DIST=scope SECTION=i ARCH=j
 378      </programlisting></para>
 379
 380      <variablelist>
 381       <varlistentry><term>Sections</term>
 382       <listitem><para>
 383       This is a space separated list of sections which appear
 384       under the distribution, typically this is something like
 385       <literal>main contrib non-free</literal></para></listitem>
 386       </varlistentry>
 387
 388       <varlistentry><term>Architectures</term>
 389       <listitem><para>
 390       This is a space separated list of all the
 391       architectures that appear under search section. The special architecture
 392       'source' is used to indicate that this tree has a source archive.</para></listitem>
 393       </varlistentry>
 394
 395       <varlistentry><term>LongDescription</term>
 396       <listitem><para>
 397       Sets if long descriptions should be included in the Packages file or split
 398       out into a master Translation-en file.</para></listitem>
 399       </varlistentry>
 400
 401       <varlistentry><term>BinOverride</term>
 402       <listitem><para>
 403       Sets the binary override file. The override file
 404       contains section, priority and maintainer address information.</para></listitem>
 405       </varlistentry>
 406
 407       <varlistentry><term>SrcOverride</term>
 408       <listitem><para>
 409       Sets the source override file. The override file
 410       contains section information.</para></listitem>
 411       </varlistentry>
 412
 413       <varlistentry><term>ExtraOverride</term>
 414       <listitem><para>
 415       Sets the binary extra override file.</para></listitem>
 416       </varlistentry>
 417
 418       <varlistentry><term>SrcExtraOverride</term>
 419       <listitem><para>
 420       Sets the source extra override file.</para></listitem>
 421       </varlistentry>
 422      </variablelist>
 423    </refsect2>
 424
 425    <refsect2><title>BinDirectory Section</title>
 426      <para>
 427      The <literal>bindirectory</literal> section defines a binary directory tree
 428      with no special structure. The scope tag specifies the location of
 429      the binary directory and the settings are similar to the <literal>Tree</literal>
 430      section with no substitution variables or
 431      <literal>Section</literal><literal>Architecture</literal> settings.</para>
 432      <variablelist>
 433       <varlistentry><term>Packages</term>
 434       <listitem><para>
 435       Sets the Packages file output.</para></listitem>
 436       </varlistentry>
 437
 438       <varlistentry><term>Sources</term>
 439       <listitem><para>
 440       Sets the Sources file output. At least one of
 441       <literal>Packages</literal> or <literal>Sources</literal> is required.</para></listitem>
 442       </varlistentry>
 443
 444       <varlistentry><term>Contents</term>
 445       <listitem><para>
 446       Sets the Contents file output. (optional)</para></listitem>
 447       </varlistentry>
 448
 449       <varlistentry><term>BinOverride</term>
 450       <listitem><para>
 451       Sets the binary override file.</para></listitem>
 452       </varlistentry>
 453
 454       <varlistentry><term>SrcOverride</term>
 455       <listitem><para>
 456       Sets the source override file.</para></listitem>
 457       </varlistentry>
 458
 459       <varlistentry><term>ExtraOverride</term>
 460       <listitem><para>
 461       Sets the binary extra override file.</para></listitem>
 462       </varlistentry>
 463
 464       <varlistentry><term>SrcExtraOverride</term>
 465       <listitem><para>
 466       Sets the source extra override file.</para></listitem>
 467       </varlistentry>
 468
 469       <varlistentry><term>BinCacheDB</term>
 470       <listitem><para>
 471       Sets the cache DB.</para></listitem>
 472       </varlistentry>
 473
 474       <varlistentry><term>PathPrefix</term>
 475       <listitem><para>
 476       Appends a path to all the output paths.</para></listitem>
 477       </varlistentry>
 478
 479       <varlistentry><term>FileList, SourceFileList</term>
 480       <listitem><para>
 481       Specifies the file list file.</para></listitem>
 482       </varlistentry>
 483      </variablelist>
 484    </refsect2>
 485  </refsect1>
 486
 487
 488  <refsect1><title>The Binary Override File</title>
 489    <para>The binary override file is fully compatible with &dpkg-scanpackages;. It
 490    contains 4 fields separated by spaces. The first field is the package name,
 491    the second is the priority to force that package to, the third is the
 492    the section to force that package to and the final field is the maintainer
 493    permutation field.</para>
 494    <para>The general form of the maintainer field is:
 495    <literallayout>old [// oldn]* => new</literallayout>
 496    or simply,
 497    <literallayout>new</literallayout>
 498    The first form allows a double-slash separated list of old email addresses
 499    to be specified. If any of those are found then new is substituted for the
 500    maintainer field. The second form unconditionally substitutes the
 501    maintainer field.</para>
 502  </refsect1>
 503
 504
 505  <refsect1><title>The Source Override File</title>
 506    <para>
 507    The source override file is fully compatible with &dpkg-scansources;. It
 508    contains 2 fields separated by spaces. The first fields is the source
 509    package name, the second is the section to assign it.</para>
 510  </refsect1>
 511
 512  <refsect1><title>The Extra Override File</title>
 513    <para>
 514    The extra override file allows any arbitrary tag to be added or replaced
 515    in the output. It has 3 columns, the first is the package, the second is
 516    the tag and the remainder of the line is the new value.</para>
 517  </refsect1>
 518
 519  <refsect1><title>options</title>
 520    &apt-cmdblurb;
 521
 522    <variablelist>
 523      <varlistentry><term><option>--md5</option></term>
 524      <listitem><para>
 525      Generate MD5 sums. This defaults to on, when turned off the generated
 526      index files will not have MD5Sum fields where possible.
 527      Configuration Item: <literal>APT::FTPArchive::MD5</literal></para></listitem>
 528      </varlistentry>
 529
 530      <varlistentry><term><option>-d</option></term><term><option>--db</option></term>
 531      <listitem><para>
 532      Use a binary caching DB. This has no effect on the generate command.
 533      Configuration Item: <literal>APT::FTPArchive::DB</literal>.</para></listitem>
 534      </varlistentry>
 535
 536      <varlistentry><term><option>-q</option></term><term><option>--quiet</option></term>
 537      <listitem><para>
 538      Quiet; produces output suitable for logging, omitting progress indicators.
 539      More q's will produce more quiet up to a maximum of 2. You can also use
 540      <option>-q=#</option> to set the quiet level, overriding the configuration file.
 541      Configuration Item: <literal>quiet</literal>.</para></listitem>
 542      </varlistentry>
 543
 544      <varlistentry><term><option>--delink</option></term>
 545      <listitem><para>
 546      Perform Delinking. If the <literal>External-Links</literal> setting is used then
 547      this option actually enables delinking of the files. It defaults to on and
 548      can be turned off with <option>--no-delink</option>.
 549      Configuration Item: <literal>APT::FTPArchive::DeLinkAct</literal>.</para></listitem>
 550      </varlistentry>
 551
 552      <varlistentry><term><option>--contents</option></term>
 553      <listitem><para>
 554      Perform contents generation. When this option is set and package indexes
 555      are being generated with a cache DB then the file listing will also be
 556      extracted and stored in the DB for later use. When using the generate
 557      command this option also allows the creation of any Contents files. The
 558      default is on.
 559      Configuration Item: <literal>APT::FTPArchive::Contents</literal>.</para></listitem>
 560      </varlistentry>
 561
 562      <varlistentry><term><option>-s</option></term><term><option>--source-override</option></term>
 563      <listitem><para>
 564      Select the source override file to use with the <literal>sources</literal> command.
 565      Configuration Item: <literal>APT::FTPArchive::SourceOverride</literal>.</para></listitem>
 566      </varlistentry>
 567
 568      <varlistentry><term><option>--readonly</option></term>
 569      <listitem><para>
 570      Make the caching databases read only.
 571      Configuration Item: <literal>APT::FTPArchive::ReadOnlyDB</literal>.</para></listitem>
 572      </varlistentry>
 573
 574      <varlistentry><term><option>-a</option></term><term><option>--arch</option></term>
 575      <listitem><para>Accept in the <literal>packages</literal> and <literal>contents</literal>
 576      commands only package files matching <literal>*_arch.deb</literal> or
 577      <literal>*_all.deb</literal> instead of all package files in the given path.
 578      Configuration Item: <literal>APT::FTPArchive::Architecture</literal>.</para></listitem>
 579      </varlistentry>
 580
 581      <varlistentry><term><option>APT::FTPArchive::AlwaysStat</option></term>
 582      <listitem><para>
 583      &apt-ftparchive; caches as much as possible of metadata in a cachedb. If packages
 584      are recompiled and/or republished with the same version again, this will lead to problems
 585      as the now outdated cached metadata like size and checksums will be used. With this option
 586      enabled this will no longer happen as it will be checked if the file was changed.
 587      Note that this option is set to "<literal>false</literal>" by default as it is not recommend
 588      to upload multiply versions/builds of a package with the same versionnumber, so in theory
 589      nobody will have these problems and therefore all these extra checks are useless.
 590      </para></listitem>
 591      </varlistentry>
 592
 593      <varlistentry><term><option>APT::FTPArchive::LongDescription</option></term>
 594      <listitem><para>
 595      This configuration option defaults to "<literal>true</literal>" and should only be set to
 596      <literal>"false"</literal> if the Archive generated with &apt-ftparchive; also provides
 597      <filename>Translation</filename> files. Note that the <filename>Translation-en</filename>
 598      master file can only be created in the generate command.
 599      </para></listitem>
 600      </varlistentry>
 601
 602      &apt-commonoptions;
 603
 604    </variablelist>
 605  </refsect1>
 606
 607 <refsect1><title>Examples</title>
 608
 609 <para>To create a compressed Packages file for a directory containing
 610 binary packages (.deb):
 611
 612 <programlisting>
 613 <command>apt-ftparchive</command> packages <replaceable>directory</replaceable> | <command>gzip</command> > <filename>Packages.gz</filename>
 614 </programlisting></para>
 615
 616 </refsect1>
 617
 618  <refsect1><title>See Also</title>
 619    <para>&apt-conf;</para>
 620  </refsect1>
 621
 622  <refsect1><title>Diagnostics</title>
 623    <para><command>apt-ftparchive</command> returns zero on normal operation, decimal 100 on error.</para>
 624  </refsect1>
 625
 626  &manbugs;
 627
 628 </refentry>