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Building Berkeley DB for Windows Mobile
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<strong>What if my Windows Mobile device does not support SetFilePointer and/or SetEndOfFile?</strong>
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<p>You can manually disable the truncate functionality from the build.</p>
<p>Do that by opening the <code class="filename">db-X.X.X/build_wince/db_config.h</code> file, and change the line that reads </p>
<pre class="programlisting">#define HAVE_FTRUCATE 1</pre>
<p> to read </p>
<pre class="programlisting">#undef HAVE_FTRUNCATE</pre>
<p>Making this change disables <a href="../api_reference/C/dbcompact.html" class="olink">DB->compact()</a> for btree databases.</p>
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<strong>Why doesn't automatic log archiving work?</strong>
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<p>The Windows Mobile platform does not have a concept of a working directory. This means that the <a href="../api_reference/C/logarchive.html#archive_DB_ARCH_REMOVE" class="olink">DB_ARCH_REMOVE</a> and <a href="../api_reference/C/logarchive.html#archive_DB_ARCH_ABS" class="olink">DB_ARCH_ABS</a> flags do not work properly within Windows Mobile, because they rely on having a working directory.</p>
<p> To work around this issue, you can call log_archive with the <a href="../api_reference/C/logarchive.html#archive_DB_ARCH_LOG" class="olink">DB_ARCH_LOG</a> flag, the list of returned file handles will not contain absolute paths. Your application can take this list of files, construct absolute paths, and delete the files.</p>
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<strong>Does Berkeley DB support Windows Mobile?</strong>
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<p>Yes. </p>
<p>Berkeley DB relies on a subset of the Windows API, and some standard C library APIs. These are provided by Windows CE. Windows Mobile is built "on top" of Windows CE.</p>
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<span class="bold">
<strong>Does Berkeley DB support Windows CE?</strong>
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<p>Yes. </p>
<p>Berkeley DB relies on a subset of the Windows API, and some standard C library APIs. These are provided by Windows CE.</p>
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<strong>What platforms are the supplied sample applications designed for?</strong>
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<p>The supplied sample applications were developed for the Pocket PC 2003 emulator. They are known to work on real pocket PC devices and later versions of the emulator as well.</p>
<p>The supplied applications are not designed to work with Smartphone devices. The screen size and input mechanisms are not compatible.</p>
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<strong>I see a file mapping error when opening a Berkeley DB environment or database. What is wrong?</strong>
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<p>The default behavior of Berkeley DB is to use memory mapped files in the environment. Windows Mobile does not allow memory mapped files to be created on flash storage.</p>
<p>There are two workarounds:</p>
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Configure the Berkeley DB environment not to use memory mapped files. The options are discussed in detail in
<a href="../programmer_reference/env_region.html" class="olink">Shared memory region</a>.
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<li>Create the Berkeley DB environment on non-flash storage. It is possible to store database and log files in a different location to using the <a href="../api_reference/C/envset_data_dir.html" class="olink">DB_ENV->set_data_dir()</a> and <a href="../api_reference/C/envset_lg_dir.html" class="olink">DB_ENV->set_lg_dir()</a> APIs.</li>
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