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<H1><A NAME="AEN1">jigdo-file</A></H1>
<DIV CLASS="REFNAMEDIV"><A NAME="AEN14"></A>
<H2>Name</H2>jigdo-file -- Prepare files for Jigsaw Download
(distribution of huge files, e.g. CD images).</DIV>
<DIV CLASS="REFSYNOPSISDIV"><A NAME="AEN17"></A>
<H2>Synopsis</H2>
<P><B CLASS="COMMAND">jigdo-file</B> { <TT CLASS="REPLACEABLE"><I>
COMMAND</I></TT> } [<TT CLASS="OPTION">--image=<TT CLASS="REPLACEABLE"
><I>cdrom.iso</I></TT></TT>] [<TT CLASS="OPTION">--jigdo=<TT
CLASS="REPLACEABLE"><I>cdrom.jigdo</I></TT></TT>] [<TT CLASS="OPTION"
>--template=<TT CLASS="REPLACEABLE"><I>cdrom.template</I></TT></TT>]
[<TT CLASS="OPTION">--force</TT>] [MORE OPTIONS] [<TT
CLASS="REPLACEABLE"><I>FILES</I></TT> | <TT CLASS="OPTION"
>--files-from=<TT CLASS="REPLACEABLE"><I>f</I></TT></TT>]<BR> Common
COMMANDs: make-template, make-image, verify </P></DIV>
<DIV CLASS="REFSECT1"><A NAME="AEN42"></A>
<H2>DESCRIPTION</H2>
<P>Jigsaw Download, or short jigdo, is a scheme developed primarily to
make it easy to distribute huge filesystem images (e.g. CD (ISO9660) or
DVD (UDF) images) over the internet, but it could also be used for
other data which is awkward to handle due to its size, like audio/video
files or large software packages.</P>
<P>jigdo tries to ensure that the large file (always called <I
CLASS="FIRSTTERM">image</I> from now on) is downloaded in small parts
which can be stored on different servers. People who want to download
the image do so by telling the <SPAN CLASS="CITEREFENTRY"><SPAN
CLASS="REFENTRYTITLE">jigdo</SPAN>(1)</SPAN> <SPAN CLASS="emphasis"><I
CLASS="EMPHASIS">(NOT IMPLEMENTED YET)</I></SPAN> download tool to
process one `<TT CLASS="FILENAME">.jigdo</TT>' file; using it, <B
CLASS="COMMAND">jigdo</B> downloads the parts and reassembles the
image. <B CLASS="COMMAND">jigdo-file</B> is used to prepare the files
for download.</P>
<P>What makes jigdo special is that the parts that are used to
reconstruct the image can have any size and content - they only need to
be contained in a contiguous region anywhere in the image.</P>
<P>For example, if you wish to distribute an ISO9660 image which
contains a snapshot of an FTP server, you can instruct <B
CLASS="COMMAND">jigdo-file</B> to prepare the download data in such a
way that when people use <B CLASS="COMMAND">jigdo</B> to download the
image, <B CLASS="COMMAND">jigdo</B> actually fetches the individual
files from the FTP server and assembles them into an exact copy of your
image - during the download! (If the image is not a filesystem dump,
you can use <SPAN CLASS="CITEREFENTRY"><SPAN CLASS="REFENTRYTITLE"
>split</SPAN>(1)</SPAN> to create the small parts that the image will
be reassembled from.)</P>
<P>You are completely free to choose where the individual parts of the
image are stored: They may be in entirely different directories on
different servers (e.g. because of storage/bandwidth constraints), but
this is invisible to the people downloading your image. The information
about available servers only needs to be added to the `<TT
CLASS="FILENAME">.jigdo</TT>' file by you before distributing it.</P>
<P>See later sections for a more detailed description of how jigdo
works, and also to get a better idea of what applications it supports
(such as customized versions of images released by others).</P></DIV>
<DIV CLASS="REFSECT1"><A NAME="AEN65"></A>
<H2>OPTIONS</H2>
<P>Many options are specific to a particular <TT CLASS="REPLACEABLE"><I
>COMMAND</I></TT>; the ones below are general or used by several
commands. Further options are listed below with the individual
commands. All options are silently ignored if they are not applicable
to the current command. For any <TT CLASS="REPLACEABLE"><I>BYTES</I
></TT> parameters to options, you can append one of the letters `k',
`M' or `G' to the amount you specify, to indicate kilobytes, megabytes
or gigabytes.</P>
<P></P>
<DIV CLASS="VARIABLELIST">
<DL>
<DT><TT CLASS="OPTION">-h</TT> <TT CLASS="OPTION">--help</TT></DT>
<DD>
<P>Output short summary of commands and options.</P></DD>
<DT><TT CLASS="OPTION">-H</TT> <TT CLASS="OPTION">--help-all</TT></DT
>
<DD>
<P>Output complete summary of commands and options.</P></DD>
<DT><TT CLASS="OPTION">-v</TT> <TT CLASS="OPTION">--version</TT></DT>
<DD>
<P>Output program version.</P></DD>
<DT><TT CLASS="OPTION">-i</TT> <TT CLASS="OPTION">--image=<TT
CLASS="REPLACEABLE"><I>cdrom.iso</I></TT></TT></DT>
<DD>
<P>Specify location of the file containing the image. The image is
the large file that you want to distribute.</P></DD>
<DT><TT CLASS="OPTION">-j</TT> <TT CLASS="OPTION">--jigdo=<TT
CLASS="REPLACEABLE"><I>cdrom.jigdo</I></TT></TT></DT>
<DD>
<P>Specify location of the Jigsaw Download description file. The
jigdo file is a human-readable file generated by <B CLASS="COMMAND"
>jigdo-file</B>, to which you add information about all the servers
you are going to upload the files to. <B CLASS="COMMAND">jigdo</B>
will download this file as the first step of retrieving the
image.</P></DD>
<DT><TT CLASS="OPTION">-t</TT> <TT CLASS="OPTION">--template=<TT
CLASS="REPLACEABLE"><I>cdrom.template</I></TT></TT></DT>
<DD>
<P>Specify location of the image `template' file. The template file
is a binary file generated by <B CLASS="COMMAND">jigdo-file</B>, it
contains information on how to reassemble the image and also (in
compressed form) all the data from the image which was not found in
any of the parts.</P>
<P>Depending on the command, each of these three files is used
sometimes for input, sometimes for output. If the file is to be used
for output for a particular command and the output file already
exists, <B CLASS="COMMAND">jigdo-file</B> exits with an error,
unless <TT CLASS="OPTION">--force</TT> is present.</P>
<P>In most cases, you will only need to specify one out of <TT
CLASS="OPTION">-i</TT> <TT CLASS="OPTION">-j</TT> <TT CLASS="OPTION"
>-t</TT>, because any missing filenames will be deduced from the one
you specify. This is done by first stripping any extension from the
supplied name and then appending nothing (if deducing <TT
CLASS="OPTION">--image</TT>), `<TT CLASS="FILENAME">.jigdo</TT>' or
`<TT CLASS="FILENAME">.template</TT>'.</P></DD>
<DT><TT CLASS="OPTION">-r</TT> <TT CLASS="OPTION"
>--report=default|noprogress|quiet|grep</TT></DT>
<DD>
<P>Control how verbose the program is, and what format the output
has: <TT CLASS="OPTION">noprogress</TT> is the same as <TT
CLASS="OPTION">default</TT> except that no `<TT
CLASS="COMPUTEROUTPUT">x% done</TT>' progress messages are printed.
<TT CLASS="OPTION">quiet</TT> restricts the output to what is
absolutely necessary, mostly error messages. <TT CLASS="OPTION"
>grep</TT> is only different from <TT CLASS="OPTION">default</TT>
for the <B CLASS="COMMAND">make-template</B> command: It enables
output in a simple `<TT CLASS="REPLACEABLE"><I><offset>
<file></I></TT>' format which is useful when searching for
binary files in other binary files.</P></DD>
<DT><TT CLASS="OPTION">-f</TT> <TT CLASS="OPTION">--force</TT></DT>
<DD>
<P>Overwrite existent output files without complaining.</P></DD>
<DT><TT CLASS="OPTION">--no-force</TT></DT>
<DD>
<P><SPAN CLASS="emphasis"><I CLASS="EMPHASIS">This is the default.</I
></SPAN> Refuse to overwrite existent output files.</P></DD>
<DT><TT CLASS="OPTION">-c</TT> <TT CLASS="OPTION">--cache=<TT
CLASS="REPLACEABLE"><I>jigdo-cache.db</I></TT></TT></DT>
<DD>
<P><B CLASS="COMMAND">jigdo-file</B> usually needs to read the entire
contents of all the <TT CLASS="REPLACEABLE"><I>FILES</I></TT> you
specify. If you use it repeatedly (e.g. because you make a new CD
image available daily), caching the file information will increase
the program's speed significantly. The cache file is automatically
created if it is not yet present. Data is usually both read from and
written to it.</P></DD>
<DT><TT CLASS="OPTION">--no-cache</TT></DT>
<DD>
<P><SPAN CLASS="emphasis"><I CLASS="EMPHASIS">This is the default.</I
></SPAN> Do not use a cache.</P></DD>
<DT><TT CLASS="OPTION">--cache-expiry=<TT CLASS="REPLACEABLE"><I
>SECONDS</I></TT></TT></DT>
<DD>
<P>Set maximum age of cache entries. Any entries older than this will
be removed from the cache. The default is 30 days. You can append
one of the letters `h', `d', `w', `m', `y' to denote hours, days,
weeks, months or years, respectively. A value of `0' or `off'
disables expiry, so that all entries will stay in the cache forever.
See the section `CACHE FILES' below for more information.</P></DD>
<DT><TT CLASS="OPTION">--readbuffer=<TT CLASS="REPLACEABLE"><I
>BYTES</I></TT></TT></DT>
<DD>
<P>Set size of internal buffers. The default is 128k - if you have a
fast disc, increasing this value may make <B CLASS="COMMAND"
>jigdo-file</B> faster, but in general, changing it is not
necessary.</P></DD>
<DT><TT CLASS="OPTION">--md5-block-size=<TT CLASS="REPLACEABLE"><I
>BYTES</I></TT></TT></DT>
<DD>
<P><SPAN CLASS="emphasis"><I CLASS="EMPHASIS">Uninteresting internal
parameter.</I></SPAN> Set size of blocks into which files are
subdivided. The default is 128k. If you change it, any cache file
will have to be regenerated. Internally, <B CLASS="COMMAND"
>jigdo-file</B> may choose to use a slightly larger or smaller
value.</P></DD>
<DT><TT CLASS="OPTION">-T</TT> <TT CLASS="OPTION">--files-from=<TT
CLASS="REPLACEABLE"><I>file</I></TT></TT></DT>
<DD>
<P>Read file and directory names from the specified file. If <TT
CLASS="REPLACEABLE"><I>file</I></TT> is `-', read names from
standard input. Each line in the file is taken as a name, so the
names may contain spaces, but not newline characters. An empty line
causes <B CLASS="COMMAND">jigdo-file</B> to stop reading from the
file.</P>
<P><SPAN CLASS="CITEREFENTRY"><SPAN CLASS="REFENTRYTITLE">find</SPAN
>(1)</SPAN> is a powerful tool for generating file lists, but make
sure to use `<B CLASS="COMMAND">find -type f</B>' if possible -
otherwise, if you instruct <B CLASS="COMMAND">find</B> to output
both a filename and a symlink to that filename, <B CLASS="COMMAND"
>jigdo-file</B> will read the file contents twice.</P></DD>
<DT><TT CLASS="REPLACEABLE"><I>FILES</I></TT></DT>
<DD>
<P>Names of files or directories to use as input. These are the parts
that are contained in the image. In case one of the names is a
directory, the program recursively scans the directory and adds all
files contained in it. While doing this, it follows symbolic links,
but avoids symlink loops.</P>
<P>If one of the filenames starts with the character `-', you must
precede the list of files with `--'. A value of `-' has <SPAN
CLASS="emphasis"><I CLASS="EMPHASIS">no</I></SPAN> special meaning
in this list, it stands for a file whose name is a single hyphen.</P
></DD></DL></DIV></DIV>
<DIV CLASS="REFSECT1"><A NAME="AEN208"></A>
<H2>COMMANDS</H2>
<P>The command name is the first non-option argument passed to <B
CLASS="COMMAND">jigdo-file</B>. Most commands have short abbreviations
as well as long names. <SPAN CLASS="emphasis"><I CLASS="EMPHASIS">The
short command names should not be used in scripts - there may be
incompatible changes to them in the future!</I></SPAN></P>
<DIV CLASS="REFSECT2"><A NAME="AEN213"></A>
<H3><B CLASS="COMMAND">make-template</B>, <B CLASS="COMMAND">mt</B
></H3>
<P>Reads <TT CLASS="REPLACEABLE"><I>image</I></TT> and <TT
CLASS="REPLACEABLE"><I>FILES</I></TT>, creates `<TT CLASS="FILENAME"
>.jigdo</TT>' and `<TT CLASS="FILENAME">.template</TT>'. This is the
main functionality of <B CLASS="COMMAND">jigdo-file</B>.</P>
<P>It is possible to specify both <TT CLASS="OPTION">--image=-</TT> and
<TT CLASS="OPTION">--files-from=-</TT>. In this case, first the list
of files is read from standard input until an empty line is
encountered. Everything following it is assumed to be the image data.
This can be useful if you use <SPAN CLASS="CITEREFENTRY"><SPAN
CLASS="REFENTRYTITLE">mkisofs</SPAN>(1)</SPAN> or similar programs
that can output the complete image on their standard output, because
there is no need to store the image on disc temporarily.</P>
<P>If a <TT CLASS="REPLACEABLE"><I>FILES</I></TT> argument contains the
characters `<TT CLASS="LITERAL">//</TT>' (Unix) or `<TT
CLASS="LITERAL">\.\</TT>' (Windows), this has special meaning. In the
final jigdo file that users will download, each of the parts is
referenced in the `[Parts]' section with a URI of the form
`Label:some/filename'. The `[Servers]' section gives a mapping of
labels to servers on the internet, with lines like
`Label=http://myserver.org/jigdofiles/'. Using this information, <B
CLASS="COMMAND">jigdo</B> will create the final download URI for the
part, `http://myserver.org/jigdofiles/some/filename'. Specifying `<TT
CLASS="LITERAL">//</TT>' (or `<TT CLASS="LITERAL">\.\</TT>') in a file
or directory name serves to `cut off' the names at the right directory
level. For example, if the Unix path of one of your <TT
CLASS="REPLACEABLE"><I>FILES</I></TT> is `/path/some/filename', you
can tell <B CLASS="COMMAND">jigdo-file</B> to cut off after the
`/path' by passing it the argument `/path//some/filename', or
`/path//' if you want the whole directory scanned. The path names need
not be absolute; `somedirectory//' is also possible.</P>
<P></P>
<DIV CLASS="VARIABLELIST">
<DL>
<DT><TT CLASS="OPTION">--label <TT CLASS="REPLACEABLE"><I
>Label=/path</I></TT></TT></DT>
<DD>
<P>Specify a name to use as the label name for a path on disc.
(Influences the output jigdo file.) If you used `<TT
CLASS="LITERAL">//</TT>' in the <TT CLASS="REPLACEABLE"><I
>FILES</I></TT> arguments as described above, <B CLASS="COMMAND"
>jigdo-file</B> will by default pick label names automatically
(`A', `B' etc.). With this option, you can give labels more
meaningful names. Note that the label name will only be used if one
or more <TT CLASS="REPLACEABLE"><I>FILES</I></TT> begin with
`/path//'.</P>
<P>Try to use label names that start with uppercase characters, to
disambiguate them clearly from protocol names like `http',
`ftp'.</P></DD>
<DT><TT CLASS="OPTION">--uri <TT CLASS="REPLACEABLE"><I
>Label=http://some.server.org/</I></TT></TT></DT>
<DD>
<P>By default, using <TT CLASS="OPTION">--label</TT> as described
above will cause lines of the form `Label=file:/path/' to be
written to the `[Servers]' section of the output jigdo file. If you
want to override the `file:' URI so that the line reads
`Label=http://some.server.org/', you can do so by specifying <TT
CLASS="OPTION">--uri</TT> along with <TT CLASS="OPTION"
>--label</TT>.</P>
<P>Note that <TT CLASS="OPTION">--uri</TT> only has an effect if the
corresponding <TT CLASS="OPTION">--label</TT> with the same label
name is present, and gets used by the program.</P>
<P>The supplied value is not quoted by the program; if it contains
characters such as space or any of the characters <TT
CLASS="LITERAL">#"'\</TT> then you must quote it. (Under Unix, you
may need to quote the value twice to also protect it from the
shell, e.g. <TT CLASS="LITERAL">\\\\</TT> or <TT CLASS="LITERAL"
>'\\'</TT> to get a single backslash in the URI.)</P>
<P>Users of the Windows version may notice that the `<TT
CLASS="LITERAL">\</TT>' directory separators are converted into
`<TT CLASS="LITERAL">/</TT>' in the `file:' URIs that are generated
by default. This is done to increase cross-platform compatibility
of `file:' - the <B CLASS="COMMAND">print-missing</B> command of
the Windows version will automatically re-convert the characters
when it prints the URIs. In case you supply your own `file:' URIs
under Windows using <TT CLASS="OPTION">--uri</TT>, you must also
exchange `<TT CLASS="LITERAL">/</TT>' and `<TT CLASS="LITERAL"
>\</TT>'.</P></DD>
<DT><TT CLASS="OPTION">-0</TT> to <TT CLASS="OPTION">-9</TT></DT>
<DD>
<P>Set amount of compression in the output template file, from <TT
CLASS="OPTION">-0</TT> (no compression) to <TT CLASS="OPTION"
>-9</TT> (maximum compression). The default is <TT CLASS="OPTION"
>-9</TT>, which can make the template generation quite slow. The
compression algorithm used is the same as for <SPAN
CLASS="CITEREFENTRY"><SPAN CLASS="REFENTRYTITLE">gzip</SPAN
>(1)</SPAN>.</P></DD>
<DT><TT CLASS="OPTION">--min-length=<TT CLASS="REPLACEABLE"><I
>BYTES</I></TT></TT></DT>
<DD>
<P>Set minimum length of a part for <B CLASS="COMMAND"
>jigdo-file</B> to look for it in the image. The default is 4k.
Parts smaller than this will never be found in the image, so their
data will be included in the template file. The search algorithm
used requires such a minimum length, otherwise template generation
could become extremely slow. If you know for sure that all your <TT
CLASS="REPLACEABLE"><I>FILES</I></TT> are larger than a certain
amount, you can increase <B CLASS="COMMAND">jigdo-file</B>'s speed
slightly by specifying the amount with this option. There is a
hard-wired absolute minimum of 1k - anything lower will silently be
set to 1k.</P></DD>
<DT><TT CLASS="OPTION">--image-section</TT></DT>
<DD>
<P><SPAN CLASS="emphasis"><I CLASS="EMPHASIS">This is the
default.</I></SPAN> Causes <B CLASS="COMMAND">jigdo-file</B> to
include an `[Image]' section in the `<TT CLASS="FILENAME"
>.jigdo</TT>' file.</P></DD>
<DT><TT CLASS="OPTION">--no-image-section</TT></DT>
<DD>
<P>Do <SPAN CLASS="emphasis"><I CLASS="EMPHASIS">not</I></SPAN>
include an `[Image]' section in the `<TT CLASS="FILENAME"
>.jigdo</TT>' file. You need to add one yourself if you use this
option.</P></DD>
<DT><TT CLASS="OPTION">--servers-section</TT></DT>
<DD>
<P><SPAN CLASS="emphasis"><I CLASS="EMPHASIS">This is the
default.</I></SPAN> Causes <B CLASS="COMMAND">jigdo-file</B> to
append a `[Servers]' section at the end of the `<TT
CLASS="FILENAME">.jigdo</TT>' file. This default section uses
`file:' URIs, which allows for immediate reassembly of the image
from the local filesystem, and is also useful if you want to edit
the file manually and replace the `file:' URIs with other URIs.</P
></DD>
<DT><TT CLASS="OPTION">--no-servers-section</TT></DT>
<DD>
<P>Do <SPAN CLASS="emphasis"><I CLASS="EMPHASIS">not</I></SPAN> add
a `[Servers]' section at the end of the `<TT CLASS="FILENAME"
>.jigdo</TT>' file. Useful e.g. if you are going to append the
section with a script.</P></DD></DL></DIV></DIV>
<DIV CLASS="REFSECT2"><A NAME="AEN324"></A>
<H3><B CLASS="COMMAND">make-image</B>, <B CLASS="COMMAND">mi</B></H3>
<P>Reads `<TT CLASS="FILENAME">.template</TT>' and <TT
CLASS="REPLACEABLE"><I>FILES</I></TT>, creates <TT CLASS="REPLACEABLE"
><I>image</I></TT> (or `<TT CLASS="FILENAME">imagename.tmp</TT>').
Provides a rudimentary way of reassembling images - <B CLASS="COMMAND"
>jigdo</B> is usually better suited for this task. However, in
contrast to <B CLASS="COMMAND">jigdo</B>, no `<TT CLASS="FILENAME"
>.jigdo</TT>' file is required.</P>
<P>If the image is to be written to a file (and not to standard
output), it is possible to create the image in several steps, with
several invocations of `<B CLASS="COMMAND">jigdo-file make-image</B
>', as follows: You first invoke <B CLASS="COMMAND">jigdo-file</B>,
specifying as many files as are available at this time. The program
scans the files, and those that are contained in the image are copied
to a temporary file, whose name is formed by appending `<TT
CLASS="FILENAME">.tmp</TT>' to the image filename.</P>
<P>For all further files which could be parts of the image, you repeat
this process. As soon as all parts are present, the temporary file
will be truncated slightly (to delete some administrative data that <B
CLASS="COMMAND">jigdo-file</B> appends at the end) and renamed to the
final image name. The possibility of reassembling the image in several
steps is especially useful for gathering files from removable media,
e.g. several older CDs.</P>
<P>Scripts using <B CLASS="COMMAND">make-image</B> can detect whether
image creation is complete by checking the exit status: 0 signals
successful creation, whereas 1 means that more files need to be
supplied. Other errors result in an exit status of 2 (`recoverable',
e.g. file not found) or 3 (non-recoverable, e.g. write error).</P>
<P></P>
<DIV CLASS="VARIABLELIST">
<DL>
<DT><TT CLASS="OPTION">--check-files</TT></DT>
<DD>
<P><SPAN CLASS="emphasis"><I CLASS="EMPHASIS">This is the
default.</I></SPAN> Whenever any part is copied to the image,
re-check its checksum against the checksum stored in the template.
It is recommended that you leave this switched on, even if it slows
down image creation a bit.</P></DD>
<DT><TT CLASS="OPTION">--no-check-files</TT></DT>
<DD>
<P>Do not check files' checksums when copying them to the image.
This can be safely used when no cache file is used (which means
that files will be written to the image immediately after being
scanned) or the whole image is checked later with the <B
CLASS="COMMAND">verify</B> command.</P></DD></DL></DIV></DIV>
<DIV CLASS="REFSECT2"><A NAME="AEN357"></A>
<H3><B CLASS="COMMAND">print-missing</B>, <B CLASS="COMMAND">pm</B
></H3>
<P>Reads `<TT CLASS="FILENAME">.jigdo</TT>', `<TT CLASS="FILENAME"
>.template</TT>' and (if present) `<TT CLASS="FILENAME"
>imagename.tmp</TT>', outputs a list of URIs still needed to
completely reassemble the image.</P>
<P>Together with the <B CLASS="COMMAND">make-image</B> command, this
provides most of the functionality of <B CLASS="COMMAND">jigdo</B> on
the command line.</P>
<P>For each part that is not yet present in the temporary image file,
the file checksum is looked up in the `[Parts]' section of the jigdo
file. Any label in the corresponding entry is then expanded according
to the label definitions in the `[Servers]' section and printed on
standard output. <B CLASS="COMMAND">jigdo</B> allows you to specify
several alternative locations for each label in this section, but <B
CLASS="COMMAND">print-missing</B> will only output the first one for
each missing part.</P>
<P>If the checksum cannot be found in the `[Parts]' section (this
Should Not Happen unless you deleted that section), a lookup is
instead made for `MD5Sum:<TT CLASS="REPLACEABLE"><I
><checksum></I></TT>', just like with <B CLASS="COMMAND"
>jigdo</B>. (Thus, if you want to get rid of the `[Parts]' section,
you can do so if you rename each part to its own checksum.)</P>
<P></P>
<DIV CLASS="VARIABLELIST">
<DL>
<DT><TT CLASS="OPTION">--uri <TT CLASS="REPLACEABLE"><I
>Label=http://some.server.org/</I></TT></TT></DT>
<DD>
<P>Override the entries in the `<TT CLASS="FILENAME">.jigdo</TT>'
file for any label with a URI of your choice. With the example
above, a `[Parts]' entry of `Label:some/filename' will cause the
line `http://some.server.org/some/filename' to be printed.</P>
<P>The supplied value is not quoted by the program; if it contains
characters such as space or any of the characters <TT
CLASS="LITERAL">#"'\</TT> then you must quote it. (Under Unix, you
may need to quote the value twice to also protect it from the
shell, e.g. <TT CLASS="LITERAL">\\\\</TT> or <TT CLASS="LITERAL"
>'\\'</TT> to get a single backslash in the URI.)</P></DD></DL
></DIV></DIV>
<DIV CLASS="REFSECT2"><A NAME="AEN386"></A>
<H3><B CLASS="COMMAND">print-missing-all</B>, <B CLASS="COMMAND"
>pma</B></H3>
<P>Just like <B CLASS="COMMAND">print-missing</B>, this command outputs
a list of URIs still needed to completely reassemble the image.
However, <SPAN CLASS="emphasis"><I CLASS="EMPHASIS">all</I></SPAN>
alternative download locations are printed instead of just one. In the
output, the URIs for a file are separated from other files' URIs with
blank lines. The <TT CLASS="OPTION">--uri</TT> option has the same
effect as for <B CLASS="COMMAND">print-missing</B>.</P></DIV>
<DIV CLASS="REFSECT2"><A NAME="AEN395"></A>
<H3><B CLASS="COMMAND">verify</B>, <B CLASS="COMMAND">ver</B></H3>
<P>Reads <TT CLASS="REPLACEABLE"><I>image</I></TT> (presumably
generated with <B CLASS="COMMAND">make-image</B>) and `<TT
CLASS="FILENAME">.template</TT>', checks for correct checksum of
image.</P>
<P>The template data does not only contain checksums of the individual
parts, but also of the image as a whole. <B CLASS="COMMAND"
>make-image</B> already performs a number of internal checks, but if
you like, you can additionally check the image with this command.</P
></DIV>
<DIV CLASS="REFSECT2"><A NAME="AEN405"></A>
<H3><B CLASS="COMMAND">scan</B>, <B CLASS="COMMAND">sc</B></H3>
<P>Reads all the <TT CLASS="REPLACEABLE"><I>FILES</I></TT> and enters
them into the cache, unless they are already cached. The <TT
CLASS="OPTION">--cache</TT> option must be present for this
command.</P></DIV>
<DIV CLASS="REFSECT2"><A NAME="AEN412"></A>
<H3><B CLASS="COMMAND">md5sum</B>, <B CLASS="COMMAND">md5</B></H3>
<P>Reads all the <TT CLASS="REPLACEABLE"><I>FILES</I></TT> and prints
out MD5 checksums of their contents. This command is quite similar to
<SPAN CLASS="CITEREFENTRY"><SPAN CLASS="REFENTRYTITLE">md5sum</SPAN
>(1)</SPAN>, except that the checksum is output in the Base64-like
encoding which is also used elsewhere by <B CLASS="COMMAND"
>jigdo-file</B>.</P>
<P>The <TT CLASS="REPLACEABLE"><I>FILES</I></TT> arguments are
processed in the same way as with the other commands, which means that
recursion automatically takes place for any arguments that are
directories, and that symbolic links are not listed except when the
file(s) they point to are not reachable directly.</P>
<P>In the checksum list printed on standard output, only the part of
the filename following any `<TT CLASS="LITERAL">//</TT>' (or `<TT
CLASS="LITERAL">\.\</TT>' on Windows) is printed. Any <TT
CLASS="OPTION">--cache</TT> will be used for querying files' MD5
checksums and/or writing the checksums of scanned files.</P></DIV>
<DIV CLASS="REFSECT2"><A NAME="AEN428"></A>
<H3><B CLASS="COMMAND">list-template</B>, <B CLASS="COMMAND">ls</B
></H3>
<P>Reads a `<TT CLASS="FILENAME">.template</TT>' file and outputs
low-level information about the image and all parts contained in it,
including offset, length and checksum.</P>
<P>You can also use this command with temporary image files (by
specifying something like <TT CLASS="OPTION"
>--template=imagename.tmp</TT>) - in that case, the output also
distinguishes between parts that have been written to the image and
parts that haven't.</P>
<P>The following different types of lines can be output. `have-file'
only occurs for `<TT CLASS="FILENAME">.tmp</TT>' files, indicating a
file that has already been successfully written to the temporary
file:</P><PRE
CLASS="SCREEN"
>in-template <TT
CLASS="REPLACEABLE"
><I
>offset-in-image length</I
></TT
>
need-file <TT
CLASS="REPLACEABLE"
><I
>offset-in-image length file-md5sum filestart-rsyncsum</I
></TT
>
have-file <TT
CLASS="REPLACEABLE"
><I
>offset-in-image length file-md5sum filestart-rsyncsum</I
></TT
>
image-info <TT
CLASS="REPLACEABLE"
><I
>image-length image-md5sum rsyncsum-size</I
></TT
></PRE></DIV></DIV>
<DIV CLASS="REFSECT1"><A NAME="AEN443"></A>
<H2>DETAILS</H2>
<P>Jigsaw Download was created with the format of ISO9660 CD images in
mind - however, the following also applies to many other filesystem
formats, as well as to `tar' archives and uncompressed `zip' archives.
A CD image contains both information for organizing the filesystem
(header with disc name etc., ISO9660 directory data, data of extensions
such as Joliet or RockRidge, zero padding) and the files contained on
the CD. An important property that jigdo relies on is that each file is
stored in one contiguous section of the image; it is not split into two
or more parts.</P>
<P>When <B CLASS="COMMAND">jigdo-file</B> is given a number of files
that might be contained in an image, it detects whether any of the
files are present using a `rolling checksum' inspired by the one used
by <SPAN CLASS="CITEREFENTRY"><SPAN CLASS="REFENTRYTITLE">rsync</SPAN
>(1)</SPAN>. The resulting data is written to the `<TT CLASS="FILENAME"
>.template</TT>' file: If a section of the image could not be matched
(e.g. it was directory information), the data is compressed and written
directly to the template. However, if a matching file was found, its
data is omitted from the template. Instead, only a reference (an MD5
checksum of the file) is inserted in the template.</P>
<P>Note that the template data only contains binary data, it does not
contain any filenames or URIs, since it cannot be easily edited in case
any of these values need to be changed. All that information is stored
in the `<TT CLASS="FILENAME">.jigdo</TT>' file, a text file to which
you can add URLs for your server(s). The jigdo file provides a mapping
for each MD5 checksum to one or more alternative download locations for
the corresponding part. See the section `FORMAT OF .JIGDO FILES' below
for details.</P>
<P>Apart from the mapping of MD5 sums to URIs, the jigdo file also
contains an URI pointing to a download location for the template file.
This way, the <B CLASS="COMMAND">jigdo</B> download tool only needs to
be given one URI (that of the `<TT CLASS="FILENAME">.jigdo</TT>' file)
to be able to download and reassemble the complete image.</P></DIV>
<DIV CLASS="REFSECT1"><A NAME="AEN457"></A>
<H2>FORMAT OF .JIGDO FILES</H2>
<P><SPAN CLASS="emphasis"><I CLASS="EMPHASIS">WORK IN PROGRESS... at the
moment, minor modifications to the format are still possible.</I
></SPAN></P>
<P>The overall format of `<TT CLASS="FILENAME">.jigdo</TT>' files
follows that of `<TT CLASS="FILENAME">.ini</TT>' files, as also used by
the Gnome and KDE projects for some data. The file is organized into
sections, each of which is preceded by a line reading `[Sectionname]'.
Within each section, lines have the form `Label=Value'. Such lines are
also called `entries' below.</P>
<P>Comments are introduced with the `<TT CLASS="LITERAL">#</TT>'
character and extend to the end of the line. Whitespace is ignored at
line start and end as well as to the left and right of section names
and the `<TT CLASS="LITERAL">=</TT>' in entries. Furthermore, the jigdo
utilities split up the text of the entry value (i.e. the part after the
`<TT CLASS="LITERAL">=</TT>') into whitespace-separated words, much
like the Unix shell. Single <TT CLASS="LITERAL">''</TT> and double <TT
CLASS="LITERAL">""</TT> quotes can be used to prevent that e.g. URIs
containing whitespace are split apart. Similarly, characters with
special meaning (the characters <TT CLASS="LITERAL">'"#\</TT> and
space/tab) must be quoted with <TT CLASS="LITERAL">\</TT> to appear in
the value. As with the shell, there is a difference between <TT
CLASS="LITERAL">''</TT> and <TT CLASS="LITERAL">""</TT>: Within <TT
CLASS="LITERAL">''</TT>, the characters <TT CLASS="LITERAL">"#\</TT>
and whitespace lose their special meaning, whereas within <TT
CLASS="LITERAL">""</TT>, only the characters <TT CLASS="LITERAL"
>'#</TT> and whitespace lose their special meaning - in other words,
backslash escapes still work inside <TT CLASS="LITERAL">""</TT>, but
not <TT CLASS="LITERAL">''</TT>.</P>
<P>Below is a description of the individual section names used by
jigdo.</P>
<DIV CLASS="REFSECT2"><A NAME="AEN481"></A>
<H3>Jigdo section</H3><PRE
CLASS="SCREEN"
>[Jigdo]
Version=1.0
Generator=jigdo-file/0.5.3
Info=<TT
CLASS="REPLACEABLE"
><I
>long description</I
></TT
></PRE>
<P>Information about the version of the jigdo file format used, and the
program that generated it. The `Info' label can contain a description
of the contents of the jigdo file.</P>
<P>There is one such section per `<TT CLASS="FILENAME">.jigdo</TT>'
file.</P></DIV>
<DIV CLASS="REFSECT2"><A NAME="AEN488"></A>
<H3>Image section</H3><PRE
CLASS="SCREEN"
>[Image]
Filename=<TT
CLASS="REPLACEABLE"
><I
>"filename for saving on user's disc"</I
></TT
>
Template=<TT
CLASS="REPLACEABLE"
><I
>"URI where to fetch template file"</I
></TT
>
Selected=yes|no
ShortInfo=<TT
CLASS="REPLACEABLE"
><I
>single-line description, for displaying menu of images</I
></TT
>
Info=<TT
CLASS="REPLACEABLE"
><I
>long description</I
></TT
></PRE>
<P>The `Selected' label indicates whether the image is selected for
download by default when <B CLASS="COMMAND">jigdo</B> is run for this
file.</P>
<P>Instead of an URI, the value for the `Template' entry can also be a
string of the form `<TT CLASS="REPLACEABLE"><I>Label</I></TT>:<TT
CLASS="REPLACEABLE"><I>pathname</I></TT>', as described below.</P>
<P>This section may occur multiple times, there is one such section for
each image in the jigdo file.</P></DIV>
<DIV CLASS="REFSECT2"><A NAME="AEN501"></A>
<H3>Parts section</H3><PRE
CLASS="SCREEN"
>[Parts]
xJNkjrq8NYMraeGavUpllw=LabelA:part0
GoTResP2EC6Lb_2wTsqOoQ=LabelA:part1
kyfebwu6clbYqqWUdFIyaw=LabelB:some/path/part2
-J9UAimo0Bqg9c0oOXI1mQ=http://some.where.com/part3</PRE>
<P>All lines in the section, which provides the mapping from MD5
checksums to URIs, have the same format: On the left side of the `<TT
CLASS="LITERAL">=</TT>' the checksum (encoded with a Base64-like
encoding) is given, and on the right a string corresponding to the
part with this checksum; either a complete URI or a string of the form
`<TT CLASS="REPLACEABLE"><I>Label</I></TT>:<TT CLASS="REPLACEABLE"><I
>pathname</I></TT>', which is expanded into one or more URIs by
looking up the definition(s) for the <TT CLASS="REPLACEABLE"><I
>Label</I></TT> in the `[Servers]' section.</P>
<P>In case a particular MD5 checksum cannot be found in any `[Parts]'
section by <B CLASS="COMMAND">jigdo</B>, the program will perform a
lookup for `<TT CLASS="LITERAL">MD5Sum:</TT><TT CLASS="REPLACEABLE"
><I><checksum></I></TT>', e.g. for `<TT CLASS="LITERAL"
>MD5Sum:xJNkjrq8NYMraeGavUpllw</TT>' if you deleted the line for
`part0' above.</P>
<P>A checksum appearing multiple times in this section indicates
alternative download locations for the part.</P>
<P>There may be any number of `[Parts]' sections in the file; they are
all considered when looking up MD5 checksums.</P></DIV>
<DIV CLASS="REFSECT2"><A NAME="AEN516"></A>
<H3>Servers section</H3><PRE
CLASS="SCREEN"
>[Servers]
LabelA=http://myserver.org/
LabelA=ftp://mirror.myserver.org/
LabelB=LabelC:subdirectory/
LabelC=http://some.where.com/jigdo/</PRE>
<P>All lines in the section, which provides the mapping from server
labels to server locations, have the same format: On the left side of
the `<TT CLASS="LITERAL">=</TT>' the label name is given, and on the
right the value to expand the label name to.</P>
<P>A label name appearing multiple times in this section indicates
alternative download locations for the parts that use the label in the
`[Parts]' section. This notation makes it very easy to add mirrors to
the jigdo file.</P>
<P>As shown by the example above, the label values may themselves
reference other labels. For example, the entry
`LabelB:some/path/part2' in the `[Parts]' section will expand to
`http://some.where.com/jigdo/subdirectory/some/path/part2'. Loops in
the label definitions result in undefined behaviour and must be
avoided.</P>
<P>There may be any number of `[Servers]' sections in the file; they
are all considered when looking up labels. Either of `[Parts]' or
`[Servers]', but not both, can be omitted from the jigdo file.</P
></DIV></DIV>
<DIV CLASS="REFSECT1"><A NAME="AEN524"></A>
<H2>CACHE FILES</H2>
<P>Any file specified with the <TT CLASS="OPTION">--cache</TT> option is
used to store information about the <TT CLASS="REPLACEABLE"><I
>FILES</I></TT> presented to <B CLASS="COMMAND">jigdo-file</B>. When
querying the cache, a file is considered unchanged (and the cached data
is used) only if filename, file size and last modification time (mtime)
match exactly. For the filename match, not the entire file name is
used, but only the part following any `<TT CLASS="LITERAL">//</TT>', so
that any changes to the part before the `<TT CLASS="LITERAL">//</TT>'
will not invalidate the cache.</P>
<P>Old cache entries are removed from the cache if they have not been
read from or written to for the amount of time specified with <TT
CLASS="OPTION">--cache-expiry</TT>. Entries are <SPAN CLASS="emphasis"
><I CLASS="EMPHASIS">not</I></SPAN> immediately removed from the cache
if the file they refer to no longer exists - this makes it possible to
cache information about files on removable media.</P>
<P>Cache expiry only takes place <SPAN CLASS="emphasis"><I
CLASS="EMPHASIS">after</I></SPAN> <B CLASS="COMMAND">jigdo-file</B> has
done its main work - if any old entries are accessed before expiry
takes place, they will be kept. For example, if the program is run
using the default expiry time of 30 days, but accesses a cache file
with entries generated 2 months ago, then entries in that cache <SPAN
CLASS="emphasis"><I CLASS="EMPHASIS">will</I></SPAN> be considered, and
only those cache entries that were not needed during the program run
will be expired.</P>
<P>Due to a peculiarity of the underlying database library (libdb3),
cache files never shrink, they only grow. If a large number of entries
was expired from your cache file and you want it to shrink, you can
either just delete it (of course then everything will have to be
regenerated) or use the utilities accompanying libdb3 to dump and
restore the database, with a command like `<B CLASS="COMMAND">db3_dump
<TT CLASS="REPLACEABLE"><I>old-cache.db</I></TT> | db3_load <TT
CLASS="REPLACEABLE"><I>new-cache.db</I></TT></B>'. <SPAN CLASS="phrase"
><SPAN CLASS="PHRASE">For Debian, these programs are supplied in the
package `libdb3-util'.</SPAN></SPAN></P>
<P>If a different <TT CLASS="OPTION">--md5-block-size</TT> is specified,
the entire file needs to be re-read to update its cache entry. If a
different <TT CLASS="OPTION">--min-length</TT> is specified, only the
first `md5-block-size' bytes of the file need to be re-read.</P></DIV>
<DIV CLASS="REFSECT1"><A NAME="AEN547"></A>
<H2>EXAMPLES</H2>
<DIV CLASS="REFSECT2"><A NAME="AEN549"></A>
<H3>Preparing your CD image for distribution</H3>
<P>You have created a CD image `<TT CLASS="FILENAME">image.iso</TT>'
from some of the files stored in the directory `<TT CLASS="FILENAME"
>/home/ftp</TT>' on your harddisc, which is also available online as
`ftp://mysite.org'. As you don't want to waste space by effectively
hosting the same data twice (once as files on the FTP server, once
inside the image), and you are fed up with users' downloads aborting
after 200MB and their restarting the download dozens of times, you
decide to use jigdo. How do you prepare the image for download?</P>
<P>In fact, only one command is necessary: <A NAME="AEN555"></A
><BLOCKQUOTE CLASS="BLOCKQUOTE">
<P><B CLASS="COMMAND">jigdo-file make-template --image=image.iso
--jigdo=/home/ftp/image.jigdo --template=/home/ftp/image.template
/home/ftp// --label Mysite=/home/ftp --uri
Mysite=ftp://mysite.org/</B></P></BLOCKQUOTE> </P>
<P>After editing the file `<TT CLASS="FILENAME"
>/home/ftp/image.jigdo</TT>' to contain the correct URI for the
template, `ftp://mysite.org/image.template', people can point <B
CLASS="COMMAND">jigdo</B> at `ftp://mysite.org/image.jigdo' to
download your image.</P>
<P>Note that nothing prevents you from doing the same for an FTP server
that isn't administrated by you - in that case, you only need to host
the `<TT CLASS="FILENAME">.jigdo</TT>' and `<TT CLASS="FILENAME"
>.template</TT>' files on your own server/homepage.</P></DIV>
<DIV CLASS="REFSECT2"><A NAME="AEN564"></A>
<H3>Preparing an arbitrary large file for distribution</H3>
<P>We assume that you have a large file that is not a filesystem, e.g.
`<TT CLASS="FILENAME">movie.mpeg</TT>'. Because of space problems, you
want to distribute the data on two servers.</P>
<P>In this case, the parts of the image need to be generated
artificially with the <B CLASS="COMMAND">split</B> command. For
example, to create chunks of 4MB each, use `<B CLASS="COMMAND">split
-b 4m movie.mpeg part</B>'. Copy the resulting files `<TT
CLASS="FILENAME">part<TT CLASS="REPLACEABLE"><I>XX</I></TT></TT>' into
two directories `<TT CLASS="FILENAME">1</TT>' and `<TT
CLASS="FILENAME">2</TT>' that you create, according to how you want
the files distributed between the servers. Next, create the jigdo and
template files with `<B CLASS="COMMAND">jigdo-file make-template
--image=movie.mpeg 1// 2//</B>'. You will need to edit the `<TT
CLASS="FILENAME">.jigdo</TT>' file and provide the right URIs for the
two servers that you are going to upload the `<TT CLASS="FILENAME"
>part<TT CLASS="REPLACEABLE"><I>XX</I></TT></TT>' files as well as the
`<TT CLASS="FILENAME">.template</TT>' file to.</P></DIV>
<DIV CLASS="REFSECT2"><A NAME="AEN580"></A>
<H3>Customized versions of images</H3>
<P>Because it is possible to assign a different URI for each part of an
image if necessary, jigdo is very flexible. Only one example is the
possibility of customized versions of images: Suppose that someone is
distributing a CD image, and that you want to make a few small changes
to it and redistribute your own version. You download the `<TT
CLASS="FILENAME">official.iso</TT>' CD image with <B CLASS="COMMAND"
>jigdo</B>, write it to CD-R, make your changes (say, adding files
from the `<TT CLASS="FILENAME">myfiles</TT>' directory on your
harddisc) and produce your own version, `<TT CLASS="FILENAME"
>myversion.iso</TT>'. Next, you instruct <B CLASS="COMMAND"
>jigdo-file</B> to create the jigdo and template files for your
modified image, using the command <A NAME="AEN588"></A><BLOCKQUOTE
CLASS="BLOCKQUOTE">
<P><B CLASS="COMMAND">jigdo-file make-template --image=myversion.iso
/mnt/cdrom/ myfiles// --label My=myfiles/ --uri
My=http://my.homepage.net/</B></P></BLOCKQUOTE> while `<TT
CLASS="FILENAME">official.iso</TT>' is mounted under `<TT
CLASS="FILENAME">/mnt/cdrom</TT>'. Now you need to create a `<TT
CLASS="FILENAME">.jigdo</TT>' file that references the same files as
the original image, but provides additional links for any files <B
CLASS="COMMAND">jigdo-file</B> picked up from the `<TT
CLASS="FILENAME">myfiles</TT>' directory. This is most easily done by
copying over the relevant sections from the jigdo file for `<TT
CLASS="FILENAME">official.iso</TT>' to your own version's jigdo
file.</P>
<P>Finally, after also adding a correct link for the template file, you
can upload the `<TT CLASS="FILENAME">.jigdo</TT>' file, the `<TT
CLASS="FILENAME">.template</TT>' file and also the files in `<TT
CLASS="FILENAME">myfiles</TT>' to `http://my.homepage.net/'. Thus, for
people to download your modified image, you do <SPAN CLASS="emphasis"
><I CLASS="EMPHASIS">not</I></SPAN> need to upload the complete image
contents to your web space, but only the changes you made!</P>
<P>(In case you only made very few changes, you could also omit the
`myfiles' parameter in the command above, then all your changes end up
in the new template file.)</P></DIV>
<DIV CLASS="REFSECT2"><A NAME="AEN603"></A>
<H3>Combining many jigdo-managed images into one</H3>
<P>It is also no problem to combine data from several sources that use
jigdo. For example, if of five different and unrelated servers each
one distributes a different CD image via jigdo, you can create a
customized DVD image that contains the data from all these CDs. When
people use <B CLASS="COMMAND">jigdo</B> to download your image, the
individual files on the DVD are fetched from the same sources as the
original CDs.</P>
<P>Consequently, even though you will be distributing a 3.2GB file via
your web space, the actual amount of data that is stored on your
server will only be in the order of several MBs.</P></DIV></DIV>
<DIV CLASS="REFSECT1"><A NAME="AEN608"></A>
<H2>BUGS</H2>
<P>For certain contents of one of the input files, most notably a
sequence of zero bytes longer than <TT CLASS="OPTION">--min-length</TT
> at the start of the file, <B CLASS="COMMAND">jigdo-file
make-template</B> may fail to find the file in the image.
Unfortunately, this restriction cannot be avoided because the program
could become very slow otherwise. <B CLASS="COMMAND">jigdo-file</B> may
also fail to find the file that <SPAN CLASS="emphasis"><I
CLASS="EMPHASIS">follows</I></SPAN> an all-zeroes file in the image. To
avoid this, exclude the all-zeroes file from <TT CLASS="REPLACEABLE"
><I>FILES</I></TT> - this means that its data will end up in the
template data, but an all-zeroes file can be compressed very well.</P>
<P>In fact, not only all-zeroes files trigger this behaviour, but also
any files which contain at their start a long sequence of short
identical strings. For example, both a file containing only `<TT
CLASS="LITERAL">a</TT>' characters and one containing `<TT
CLASS="LITERAL">abcabcabcabc</TT>...' are problematic.</P></DIV>
<DIV CLASS="REFSECT1"><A NAME="AEN619"></A>
<H2>SEE ALSO</H2>
<P> <SPAN CLASS="CITEREFENTRY"><SPAN CLASS="REFENTRYTITLE">jigdo</SPAN
>(1)</SPAN> (NOT YET IMPLEMENTED), <SPAN CLASS="CITEREFENTRY"><SPAN
CLASS="REFENTRYTITLE">split</SPAN>(1)</SPAN> (or `<B CLASS="COMMAND"
>info split</B>'), <SPAN CLASS="CITEREFENTRY"><SPAN
CLASS="REFENTRYTITLE">find</SPAN>(1)</SPAN> (or `<B CLASS="COMMAND"
>info find</B>'), <SPAN CLASS="CITEREFENTRY"><SPAN
CLASS="REFENTRYTITLE">mkisofs</SPAN>(1)</SPAN>, <SPAN
CLASS="CITEREFENTRY"><SPAN CLASS="REFENTRYTITLE">md5sum</SPAN
>(1)</SPAN> </P></DIV>
<DIV CLASS="REFSECT1"><A NAME="AEN639"></A>
<H2>AUTHOR</H2>
<P><A HREF="http://atterer.net/jigdo/" TARGET="_top">Jigsaw Download</A
> was written by Richard Atterer <TT CLASS="EMAIL"><<A
HREF="mailto:jigdo@atterer.net">jigdo@atterer.net</A>></TT>, to
make downloading of CD ROM images for the Debian GNU/Linux distribution
more convenient.</P></DIV>
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