doc/apt-ftparchive.1.xml

   1 <?xml version="1.0" encoding="utf-8" standalone="no"?>
   2 <!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
   3   "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd" [
   4
   5 <!ENTITY % aptent SYSTEM "apt.ent">
   6 %aptent;
   7
   8 ]>
   9
  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>Architectures</literal>, <literal>Components</literal>, <literal>Description</literal>.</para></listitem>
 126
 127      </varlistentry>
 128
 129      <varlistentry><term>generate</term>
 130      <listitem><para>
 131      The <literal>generate</literal> command is designed to be runnable from a cron script and
 132      builds indexes according to the given config file. The config language
 133      provides a flexible means of specifying which index files are built from
 134      which directories, as well as providing a simple means of maintaining the
 135      required settings.</para></listitem>
 136      </varlistentry>
 137
 138      <varlistentry><term>clean</term>
 139      <listitem><para>
 140      The <literal>clean</literal> command tidies the databases used by the given
 141      configuration file by removing any records that are no longer necessary.</para></listitem>
 142      </varlistentry>
 143    </variablelist>
 144  </refsect1>
 145
 146  <refsect1><title>The Generate Configuration</title>
 147    <para>
 148    The <literal>generate</literal> command uses a configuration file to describe the
 149    archives that are going to be generated. It follows the typical ISC
 150    configuration format as seen in ISC tools like bind 8 and dhcpd.
 151    &apt-conf; contains a description of the syntax. Note that the generate
 152    configuration is parsed in sectional manner, but &apt-conf; is parsed in a
 153    tree manner. This only effects how the scope tag is handled.</para>
 154
 155    <para>
 156    The generate configuration has 4 separate sections, each described below.</para>
 157
 158    <refsect2><title>Dir Section</title>
 159      <para>
 160      The <literal>Dir</literal> section defines the standard directories needed to
 161      locate the files required during the generation process. These
 162      directories are prepended certain relative paths defined in later
 163      sections to produce a complete an absolute path.</para>
 164      <variablelist>
 165       <varlistentry><term>ArchiveDir</term>
 166       <listitem><para>
 167       Specifies the root of the FTP archive, in a standard
 168       Debian configuration this is the directory that contains the
 169       <filename>ls-LR</filename> and dist nodes.</para></listitem>
 170       </varlistentry>
 171
 172       <varlistentry><term>OverrideDir</term>
 173       <listitem><para>
 174       Specifies the location of the override files.</para></listitem>
 175       </varlistentry>
 176
 177       <varlistentry><term>CacheDir</term>
 178       <listitem><para>
 179       Specifies the location of the cache files</para></listitem>
 180       </varlistentry>
 181
 182       <varlistentry><term>FileListDir</term>
 183       <listitem><para>
 184       Specifies the location of the file list files,
 185       if the <literal>FileList</literal> setting is used below.</para></listitem>
 186       </varlistentry>
 187      </variablelist>
 188    </refsect2>
 189
 190    <refsect2><title>Default Section</title>
 191      <para>
 192      The <literal>Default</literal> section specifies default values, and settings
 193      that control the operation of the generator. Other sections may override
 194      these defaults with a per-section setting.</para>
 195      <variablelist>
 196       <varlistentry><term>Packages::Compress</term>
 197       <listitem><para>
 198       Sets the default compression schemes to use
 199       for the Package index files. It is a string that contains a space
 200       separated list of at least one of: '.' (no compression), 'gzip' and
 201       'bzip2'. The default for all compression schemes is '. gzip'.</para></listitem>
 202       </varlistentry>
 203
 204       <varlistentry><term>Packages::Extensions</term>
 205       <listitem><para>
 206       Sets the default list of file extensions that are package files.
 207       This defaults to '.deb'.</para></listitem>
 208       </varlistentry>
 209
 210       <varlistentry><term>Sources::Compress</term>
 211       <listitem><para>
 212       This is similar to <literal>Packages::Compress</literal>
 213       except that it controls the compression for the Sources files.</para></listitem>
 214       </varlistentry>
 215
 216       <varlistentry><term>Sources::Extensions</term>
 217       <listitem><para>
 218       Sets the default list of file extensions that are source files.
 219       This defaults to '.dsc'.</para></listitem>
 220       </varlistentry>
 221
 222       <varlistentry><term>Contents::Compress</term>
 223       <listitem><para>
 224       This is similar to <literal>Packages::Compress</literal>
 225       except that it controls the compression for the Contents files.</para></listitem>
 226       </varlistentry>
 227
 228       <varlistentry><term>Translation::Compress</term>
 229       <listitem><para>
 230       This is similar to <literal>Packages::Compress</literal>
 231       except that it controls the compression for the Translation-en master file.</para></listitem>
 232       </varlistentry>
 233
 234       <varlistentry><term>DeLinkLimit</term>
 235       <listitem><para>
 236       Specifies the number of kilobytes to delink (and
 237       replace with hard links) per run. This is used in conjunction with the
 238       per-section <literal>External-Links</literal> setting.</para></listitem>
 239       </varlistentry>
 240
 241       <varlistentry><term>FileMode</term>
 242       <listitem><para>
 243       Specifies the mode of all created index files. It
 244       defaults to 0644. All index files are set to this mode with no regard
 245       to the umask.</para></listitem>
 246       </varlistentry>
 247
 248       <varlistentry><term>LongDescription</term>
 249       <listitem><para>
 250       Sets if long descriptions should be included in the Packages file or split
 251       out into a master Translation-en file.</para></listitem>
 252       </varlistentry>
 253      </variablelist>
 254    </refsect2>
 255
 256    <refsect2><title>TreeDefault Section</title>
 257      <para>
 258      Sets defaults specific to <literal>Tree</literal> sections. All of these
 259      variables are substitution variables and have the strings $(DIST),
 260      $(SECTION) and $(ARCH) replaced with their respective values.</para>
 261
 262      <variablelist>
 263       <varlistentry><term>MaxContentsChange</term>
 264       <listitem><para>
 265       Sets  the number of kilobytes of contents
 266       files that are generated each day. The contents files are round-robined
 267       so that over several days they will all be rebuilt.</para></listitem>
 268       </varlistentry>
 269
 270       <varlistentry><term>ContentsAge</term>
 271       <listitem><para>
 272       Controls the number of days a contents file is allowed
 273       to be checked without changing. If this limit is passed the mtime of the
 274       contents file is updated. This case can occur if the package file is
 275       changed in such a way that does not result in a new contents file
 276       [override edit for instance]. A hold off is allowed in hopes that new
 277       .debs will be installed, requiring a new file anyhow. The default is 10,
 278       the units are in days.</para></listitem>
 279       </varlistentry>
 280
 281       <varlistentry><term>Directory</term>
 282       <listitem><para>
 283       Sets the top of the .deb directory tree. Defaults to
 284       <filename>$(DIST)/$(SECTION)/binary-$(ARCH)/</filename></para></listitem>
 285       </varlistentry>
 286
 287       <varlistentry><term>SrcDirectory</term>
 288       <listitem><para>
 289       Sets the top of the source package directory tree. Defaults to
 290       <filename>$(DIST)/$(SECTION)/source/</filename></para></listitem>
 291       </varlistentry>
 292
 293       <varlistentry><term>Packages</term>
 294       <listitem><para>
 295       Sets the output Packages file. Defaults to
 296       <filename>$(DIST)/$(SECTION)/binary-$(ARCH)/Packages</filename></para></listitem>
 297       </varlistentry>
 298
 299       <varlistentry><term>Sources</term>
 300       <listitem><para>
 301       Sets the output Sources file. Defaults to
 302       <filename>$(DIST)/$(SECTION)/source/Sources</filename></para></listitem>
 303       </varlistentry>
 304
 305       <varlistentry><term>Translation</term>
 306       <listitem><para>
 307       Set the output Translation-en master file with the long descriptions if they
 308       should be not included in the Packages file. Defaults to
 309       <filename>$(DIST)/$(SECTION)/i18n/Translation-en</filename></para></listitem>
 310       </varlistentry>
 311
 312       <varlistentry><term>InternalPrefix</term>
 313       <listitem><para>
 314       Sets the path prefix that causes a symlink to be
 315       considered an internal link instead of an external link. Defaults to
 316       <filename>$(DIST)/$(SECTION)/</filename></para></listitem>
 317       </varlistentry>
 318
 319       <varlistentry><term>Contents</term>
 320       <listitem><para>
 321       Sets the output Contents file. Defaults to
 322       <filename>$(DIST)/Contents-$(ARCH)</filename>. If this setting causes multiple
 323       Packages files to map onto a single Contents file (such as the default)
 324       then <command>apt-ftparchive</command> will integrate those package files
 325       together automatically.</para></listitem>
 326       </varlistentry>
 327
 328       <varlistentry><term>Contents::Header</term>
 329       <listitem><para>
 330       Sets header file to prepend to the contents output.</para></listitem>
 331       </varlistentry>
 332
 333       <varlistentry><term>BinCacheDB</term>
 334       <listitem><para>
 335       Sets the binary cache database to use for this
 336       section. Multiple sections can share the same database.</para></listitem>
 337       </varlistentry>
 338
 339       <varlistentry><term>FileList</term>
 340       <listitem><para>
 341       Specifies that instead of walking the directory tree,
 342       <command>apt-ftparchive</command> should read the list of files from the given
 343       file. Relative files names are prefixed with the archive directory.</para></listitem>
 344       </varlistentry>
 345
 346       <varlistentry><term>SourceFileList</term>
 347       <listitem><para>
 348       Specifies that instead of walking the directory tree,
 349       <command>apt-ftparchive</command> should read the list of files from the given
 350       file. Relative files names are prefixed with the archive directory.
 351       This is used when processing source indexes.</para></listitem>
 352       </varlistentry>
 353      </variablelist>
 354    </refsect2>
 355
 356    <refsect2><title>Tree Section</title>
 357      <para>
 358      The <literal>Tree</literal> section defines a standard Debian file tree which
 359      consists of a base directory, then multiple sections in that base
 360      directory and finally multiple Architectures in each section. The exact
 361      pathing used is defined by the <literal>Directory</literal> substitution variable.</para>
 362      <para>
 363      The <literal>Tree</literal> section takes a scope tag which sets the
 364      <literal>$(DIST)</literal> variable and defines the root of the tree
 365      (the path is prefixed by <literal>ArchiveDir</literal>).
 366      Typically this is a setting such as <filename>dists/&stable-codename;</filename>.</para>
 367      <para>
 368      All of the settings defined in the <literal>TreeDefault</literal> section can be
 369      use in a <literal>Tree</literal> section as well as three new variables.</para>
 370      <para>
 371      When processing a <literal>Tree</literal> section <command>apt-ftparchive</command>
 372      performs an operation similar to:
 373      <programlisting>
 374 for i in Sections do
 375    for j in Architectures do
 376       Generate for DIST=scope SECTION=i ARCH=j
 377      </programlisting></para>
 378
 379      <variablelist>
 380       <varlistentry><term>Sections</term>
 381       <listitem><para>
 382       This is a space separated list of sections which appear
 383       under the distribution, typically this is something like
 384       <literal>main contrib non-free</literal></para></listitem>
 385       </varlistentry>
 386
 387       <varlistentry><term>Architectures</term>
 388       <listitem><para>
 389       This is a space separated list of all the
 390       architectures that appear under search section. The special architecture
 391       'source' is used to indicate that this tree has a source archive.</para></listitem>
 392       </varlistentry>
 393
 394       <varlistentry><term>LongDescription</term>
 395       <listitem><para>
 396       Sets if long descriptions should be included in the Packages file or split
 397       out into a master Translation-en file.</para></listitem>
 398       </varlistentry>
 399
 400       <varlistentry><term>BinOverride</term>
 401       <listitem><para>
 402       Sets the binary override file. The override file
 403       contains section, priority and maintainer address information.</para></listitem>
 404       </varlistentry>
 405
 406       <varlistentry><term>SrcOverride</term>
 407       <listitem><para>
 408       Sets the source override file. The override file
 409       contains section information.</para></listitem>
 410       </varlistentry>
 411
 412       <varlistentry><term>ExtraOverride</term>
 413       <listitem><para>
 414       Sets the binary extra override file.</para></listitem>
 415       </varlistentry>
 416
 417       <varlistentry><term>SrcExtraOverride</term>
 418       <listitem><para>
 419       Sets the source extra override file.</para></listitem>
 420       </varlistentry>
 421      </variablelist>
 422    </refsect2>
 423
 424    <refsect2><title>BinDirectory Section</title>
 425      <para>
 426      The <literal>bindirectory</literal> section defines a binary directory tree
 427      with no special structure. The scope tag specifies the location of
 428      the binary directory and the settings are similar to the <literal>Tree</literal>
 429      section with no substitution variables or
 430      <literal>Section</literal><literal>Architecture</literal> settings.</para>
 431      <variablelist>
 432       <varlistentry><term>Packages</term>
 433       <listitem><para>
 434       Sets the Packages file output.</para></listitem>
 435       </varlistentry>
 436
 437       <varlistentry><term>Sources</term>
 438       <listitem><para>
 439       Sets the Sources file output. At least one of
 440       <literal>Packages</literal> or <literal>Sources</literal> is required.</para></listitem>
 441       </varlistentry>
 442
 443       <varlistentry><term>Contents</term>
 444       <listitem><para>
 445       Sets the Contents file output. (optional)</para></listitem>
 446       </varlistentry>
 447
 448       <varlistentry><term>BinOverride</term>
 449       <listitem><para>
 450       Sets the binary override file.</para></listitem>
 451       </varlistentry>
 452
 453       <varlistentry><term>SrcOverride</term>
 454       <listitem><para>
 455       Sets the source override file.</para></listitem>
 456       </varlistentry>
 457
 458       <varlistentry><term>ExtraOverride</term>
 459       <listitem><para>
 460       Sets the binary extra override file.</para></listitem>
 461       </varlistentry>
 462
 463       <varlistentry><term>SrcExtraOverride</term>
 464       <listitem><para>
 465       Sets the source extra override file.</para></listitem>
 466       </varlistentry>
 467
 468       <varlistentry><term>BinCacheDB</term>
 469       <listitem><para>
 470       Sets the cache DB.</para></listitem>
 471       </varlistentry>
 472
 473       <varlistentry><term>PathPrefix</term>
 474       <listitem><para>
 475       Appends a path to all the output paths.</para></listitem>
 476       </varlistentry>
 477
 478       <varlistentry><term>FileList, SourceFileList</term>
 479       <listitem><para>
 480       Specifies the file list file.</para></listitem>
 481       </varlistentry>
 482      </variablelist>
 483    </refsect2>
 484  </refsect1>
 485
 486
 487  <refsect1><title>The Binary Override File</title>
 488    <para>The binary override file is fully compatible with &dpkg-scanpackages;. It
 489    contains 4 fields separated by spaces. The first field is the package name,
 490    the second is the priority to force that package to, the third is the
 491    the section to force that package to and the final field is the maintainer
 492    permutation field.</para>
 493    <para>The general form of the maintainer field is:
 494    <literallayout>old [// oldn]* => new</literallayout>
 495    or simply,
 496    <literallayout>new</literallayout>
 497    The first form allows a double-slash separated list of old email addresses
 498    to be specified. If any of those are found then new is substituted for the
 499    maintainer field. The second form unconditionally substitutes the
 500    maintainer field.</para>
 501  </refsect1>
 502
 503
 504  <refsect1><title>The Source Override File</title>
 505    <para>
 506    The source override file is fully compatible with &dpkg-scansources;. It
 507    contains 2 fields separated by spaces. The first fields is the source
 508    package name, the second is the section to assign it.</para>
 509  </refsect1>
 510
 511  <refsect1><title>The Extra Override File</title>
 512    <para>
 513    The extra override file allows any arbitrary tag to be added or replaced
 514    in the output. It has 3 columns, the first is the package, the second is
 515    the tag and the remainder of the line is the new value.</para>
 516  </refsect1>
 517
 518  <refsect1><title>options</title>
 519    &apt-cmdblurb;
 520
 521    <variablelist>
 522      <varlistentry><term><option>--md5</option></term>
 523      <listitem><para>
 524      Generate MD5 sums. This defaults to on, when turned off the generated
 525      index files will not have MD5Sum fields where possible.
 526      Configuration Item: <literal>APT::FTPArchive::MD5</literal></para></listitem>
 527      </varlistentry>
 528
 529      <varlistentry><term><option>-d</option></term><term><option>--db</option></term>
 530      <listitem><para>
 531      Use a binary caching DB. This has no effect on the generate command.
 532      Configuration Item: <literal>APT::FTPArchive::DB</literal>.</para></listitem>
 533      </varlistentry>
 534
 535      <varlistentry><term><option>-q</option></term><term><option>--quiet</option></term>
 536      <listitem><para>
 537      Quiet; produces output suitable for logging, omitting progress indicators.
 538      More q's will produce more quiet up to a maximum of 2. You can also use
 539      <option>-q=#</option> to set the quiet level, overriding the configuration file.
 540      Configuration Item: <literal>quiet</literal>.</para></listitem>
 541      </varlistentry>
 542
 543      <varlistentry><term><option>--delink</option></term>
 544      <listitem><para>
 545      Perform Delinking. If the <literal>External-Links</literal> setting is used then
 546      this option actually enables delinking of the files. It defaults to on and
 547      can be turned off with <option>--no-delink</option>.
 548      Configuration Item: <literal>APT::FTPArchive::DeLinkAct</literal>.</para></listitem>
 549      </varlistentry>
 550
 551      <varlistentry><term><option>--contents</option></term>
 552      <listitem><para>
 553      Perform contents generation. When this option is set and package indexes
 554      are being generated with a cache DB then the file listing will also be
 555      extracted and stored in the DB for later use. When using the generate
 556      command this option also allows the creation of any Contents files. The
 557      default is on.
 558      Configuration Item: <literal>APT::FTPArchive::Contents</literal>.</para></listitem>
 559      </varlistentry>
 560
 561      <varlistentry><term><option>-s</option></term><term><option>--source-override</option></term>
 562      <listitem><para>
 563      Select the source override file to use with the <literal>sources</literal> command.
 564      Configuration Item: <literal>APT::FTPArchive::SourceOverride</literal>.</para></listitem>
 565      </varlistentry>
 566
 567      <varlistentry><term><option>--readonly</option></term>
 568      <listitem><para>
 569      Make the caching databases read only.
 570      Configuration Item: <literal>APT::FTPArchive::ReadOnlyDB</literal>.</para></listitem>
 571      </varlistentry>
 572
 573      <varlistentry><term><option>-a</option></term><term><option>--arch</option></term>
 574      <listitem><para>Accept in the <literal>packages</literal> and <literal>contents</literal>
 575      commands only package files matching <literal>*_arch.deb</literal> or
 576      <literal>*_all.deb</literal> instead of all package files in the given path.
 577      Configuration Item: <literal>APT::FTPArchive::Architecture</literal>.</para></listitem>
 578      </varlistentry>
 579
 580      <varlistentry><term><option>APT::FTPArchive::AlwaysStat</option></term>
 581      <listitem><para>
 582      &apt-ftparchive; caches as much as possible of metadata in a cachedb. If packages
 583      are recompiled and/or republished with the same version again, this will lead to problems
 584      as the now outdated cached metadata like size and checksums will be used. With this option
 585      enabled this will no longer happen as it will be checked if the file was changed.
 586      Note that this option is set to "<literal>false</literal>" by default as it is not recommend
 587      to upload multiply versions/builds of a package with the same versionnumber, so in theory
 588      nobody will have these problems and therefore all these extra checks are useless.
 589      </para></listitem>
 590      </varlistentry>
 591
 592      <varlistentry><term><option>APT::FTPArchive::LongDescription</option></term>
 593      <listitem><para>
 594      This configuration option defaults to "<literal>true</literal>" and should only be set to
 595      <literal>"false"</literal> if the Archive generated with &apt-ftparchive; also provides
 596      <filename>Translation</filename> files. Note that the <filename>Translation-en</filename>
 597      master file can only be created in the generate command.
 598      </para></listitem>
 599      </varlistentry>
 600
 601      &apt-commonoptions;
 602
 603    </variablelist>
 604  </refsect1>
 605
 606 <refsect1><title>Examples</title>
 607
 608 <para>To create a compressed Packages file for a directory containing
 609 binary packages (.deb):
 610
 611 <programlisting>
 612 <command>apt-ftparchive</command> packages <replaceable>directory</replaceable> | <command>gzip</command> > <filename>Packages.gz</filename>
 613 </programlisting></para>
 614
 615 </refsect1>
 616
 617  <refsect1><title>See Also</title>
 618    <para>&apt-conf;</para>
 619  </refsect1>
 620
 621  <refsect1><title>Diagnostics</title>
 622    <para><command>apt-ftparchive</command> returns zero on normal operation, decimal 100 on error.</para>
 623  </refsect1>
 624
 625  &manbugs;
 626
 627 </refentry>