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- The <code class="filename">libecpg</code> library primarily contains
- <span class="quote">“<span class="quote">hidden</span>”</span> functions that are used to implement the
- functionality expressed by the embedded SQL commands. But there
- are some functions that can usefully be called directly. Note that
- this makes your code unportable.
- </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
- <code class="function">ECPGdebug(int <em class="replaceable"><code>on</code></em>, FILE
- *<em class="replaceable"><code>stream</code></em>)</code> turns on debug
- logging if called with the first argument non-zero. Debug logging
- is done on <em class="replaceable"><code>stream</code></em>. The log contains
- all <acronym class="acronym">SQL</acronym> statements with all the input
- variables inserted, and the results from the
- <span class="productname">PostgreSQL</span> server. This can be very
- useful when searching for errors in your <acronym class="acronym">SQL</acronym>
- statements.
- </p><div class="note"><h3 class="title">Note</h3><p>
- On Windows, if the <span class="application">ecpg</span> libraries and an application are
- compiled with different flags, this function call will crash the
- application because the internal representation of the
- <code class="literal">FILE</code> pointers differ. Specifically,
- multithreaded/single-threaded, release/debug, and static/dynamic
- flags should be the same for the library and all applications using
- that library.
- </p></div></li><li class="listitem"><p>
- <code class="function">ECPGget_PGconn(const char *<em class="replaceable"><code>connection_name</code></em>)
- </code> returns the library database connection handle identified by the given name.
- If <em class="replaceable"><code>connection_name</code></em> is set to <code class="literal">NULL</code>, the current
- connection handle is returned. If no connection handle can be identified, the function returns
- <code class="literal">NULL</code>. The returned connection handle can be used to call any other functions
- from <span class="application">libpq</span>, if necessary.
- </p><div class="note"><h3 class="title">Note</h3><p>
- It is a bad idea to manipulate database connection handles made from <span class="application">ecpg</span> directly
- with <span class="application">libpq</span> routines.
- </p></div></li><li class="listitem"><p>
- <code class="function">ECPGtransactionStatus(const char *<em class="replaceable"><code>connection_name</code></em>)</code>
- returns the current transaction status of the given connection identified by <em class="replaceable"><code>connection_name</code></em>.
- See <a class="xref" href="libpq-status.html" title="33.2. Connection Status Functions">Section 33.2</a> and libpq's <code class="function">PQtransactionStatus()</code> for details about the returned status codes.
- </p></li><li class="listitem"><p>
- <code class="function">ECPGstatus(int <em class="replaceable"><code>lineno</code></em>,
- const char* <em class="replaceable"><code>connection_name</code></em>)</code>
- returns true if you are connected to a database and false if not.
- <em class="replaceable"><code>connection_name</code></em> can be <code class="literal">NULL</code>
- if a single connection is being used.
- </p></li></ul></div></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="ecpg-process.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="ecpg.html">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="ecpg-lo.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">35.10. Processing Embedded SQL Programs </td><td width="20%" align="center"><a accesskey="h" href="index.html">Home</a></td><td width="40%" align="right" valign="top"> 35.12. Large Objects</td></tr></table></div></body></html>
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