| <?xml version="1.0" encoding="UTF-8" standalone="no"?> |
| <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /><title>ecpg</title><link rel="stylesheet" type="text/css" href="stylesheet.css" /><link rev="made" href="pgsql-docs@lists.postgresql.org" /><meta name="generator" content="DocBook XSL Stylesheets Vsnapshot" /><link rel="prev" href="app-dropuser.html" title="dropuser" /><link rel="next" href="app-pgamcheck.html" title="pg_amcheck" /></head><body id="docContent" class="container-fluid col-10"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="5" align="center"><span class="application">ecpg</span></th></tr><tr><td width="10%" align="left"><a accesskey="p" href="app-dropuser.html" title="dropuser">Prev</a> </td><td width="10%" align="left"><a accesskey="u" href="reference-client.html" title="PostgreSQL Client Applications">Up</a></td><th width="60%" align="center">PostgreSQL Client Applications</th><td width="10%" align="right"><a accesskey="h" href="index.html" title="PostgreSQL 16.3 Documentation">Home</a></td><td width="10%" align="right"> <a accesskey="n" href="app-pgamcheck.html" title="pg_amcheck">Next</a></td></tr></table><hr /></div><div class="refentry" id="APP-ECPG"><div class="titlepage"></div><a id="id-1.9.4.8.1" class="indexterm"></a><div class="refnamediv"><h2><span class="refentrytitle"><span class="application">ecpg</span></span></h2><p><span class="application">ecpg</span> — embedded SQL C preprocessor</p></div><div class="refsynopsisdiv"><h2>Synopsis</h2><div class="cmdsynopsis"><p id="id-1.9.4.8.4.1"><code class="command">ecpg</code> [<em class="replaceable"><code>option</code></em>...] <em class="replaceable"><code>file</code></em>... </p></div></div><div class="refsect1" id="APP-ECPG-DESCRIPTION"><h2>Description</h2><p> |
| <code class="command">ecpg</code> is the embedded SQL preprocessor for C |
| programs. It converts C programs with embedded SQL statements to |
| normal C code by replacing the SQL invocations with special |
| function calls. The output files can then be processed with any C |
| compiler tool chain. |
| </p><p> |
| <code class="command">ecpg</code> will convert each input file given on the |
| command line to the corresponding C output file. If an input file |
| name does not have any extension, <code class="filename">.pgc</code> is |
| assumed. The file's extension will be replaced |
| by <code class="filename">.c</code> to construct the output file name. |
| But the output file name can be overridden using the |
| <code class="option">-o</code> option. |
| </p><p> |
| If an input file name is just <code class="literal">-</code>, |
| <code class="command">ecpg</code> reads the program from standard input |
| (and writes to standard output, unless that is overridden |
| with <code class="option">-o</code>). |
| </p><p> |
| This reference page does not describe the embedded SQL language. |
| See <a class="xref" href="ecpg.html" title="Chapter 36. ECPG — Embedded SQL in C">Chapter 36</a> for more information on that topic. |
| </p></div><div class="refsect1" id="id-1.9.4.8.6"><h2>Options</h2><p> |
| <code class="command">ecpg</code> accepts the following command-line |
| arguments: |
|
|
| </p><div class="variablelist"><dl class="variablelist"><dt><span class="term"><code class="option">-c</code></span></dt><dd><p> |
| Automatically generate certain C code from SQL code. Currently, this |
| works for <code class="literal">EXEC SQL TYPE</code>. |
| </p></dd><dt><span class="term"><code class="option">-C <em class="replaceable"><code>mode</code></em></code></span></dt><dd><p> |
| Set a compatibility mode. <em class="replaceable"><code>mode</code></em> can |
| be <code class="literal">INFORMIX</code>, |
| <code class="literal">INFORMIX_SE</code>, or <code class="literal">ORACLE</code>. |
| </p></dd><dt><span class="term"><code class="option">-D <em class="replaceable"><code>symbol</code></em>[=<em class="replaceable"><code>value</code></em>]</code></span></dt><dd><p> |
| Define a preprocessor symbol, equivalently to the <code class="command">EXEC SQL |
| DEFINE</code> directive. If no <em class="replaceable"><code>value</code></em> is |
| specified, the symbol is defined with the value <code class="literal">1</code>. |
| </p></dd><dt><span class="term"><code class="option">-h</code></span></dt><dd><p> |
| Process header files. When this option is specified, the output file |
| extension becomes <code class="literal">.h</code> not <code class="literal">.c</code>, |
| and the default input file extension is <code class="literal">.pgh</code> |
| not <code class="literal">.pgc</code>. Also, the <code class="option">-c</code> option is |
| forced on. |
| </p></dd><dt><span class="term"><code class="option">-i</code></span></dt><dd><p> |
| Parse system include files as well. |
| </p></dd><dt><span class="term"><code class="option">-I <em class="replaceable"><code>directory</code></em></code></span></dt><dd><p> |
| Specify an additional include path, used to find files included |
| via <code class="literal">EXEC SQL INCLUDE</code>. Defaults are |
| <code class="filename">.</code> (current directory), |
| <code class="filename">/usr/local/include</code>, the |
| <span class="productname">PostgreSQL</span> include directory which |
| is defined at compile time (default: |
| <code class="filename">/usr/local/pgsql/include</code>), and |
| <code class="filename">/usr/include</code>, in that order. |
| </p></dd><dt><span class="term"><code class="option">-o <em class="replaceable"><code>filename</code></em></code></span></dt><dd><p> |
| Specifies that <code class="command">ecpg</code> should write all |
| its output to the given <em class="replaceable"><code>filename</code></em>. |
| Write <code class="literal">-o -</code> to send all output to standard output. |
| </p></dd><dt><span class="term"><code class="option">-r <em class="replaceable"><code>option</code></em></code></span></dt><dd><p> |
| Selects run-time behavior. <em class="replaceable"><code>Option</code></em> can be |
| one of the following: |
| </p><div class="variablelist"><dl class="variablelist"><dt><span class="term"><code class="option">no_indicator</code></span></dt><dd><p> |
| Do not use indicators but instead use special values to represent |
| null values. Historically there have been databases using this approach. |
| </p></dd><dt><span class="term"><code class="option">prepare</code></span></dt><dd><p> |
| Prepare all statements before using them. Libecpg will keep a cache of |
| prepared statements and reuse a statement if it gets executed again. If the |
| cache runs full, libecpg will free the least used statement. |
| </p></dd><dt><span class="term"><code class="option">questionmarks</code></span></dt><dd><p> |
| Allow question mark as placeholder for compatibility reasons. |
| This used to be the default long ago. |
| </p></dd></dl></div></dd><dt><span class="term"><code class="option">-t</code></span></dt><dd><p> |
| Turn on autocommit of transactions. In this mode, each SQL command is |
| automatically committed unless it is inside an explicit |
| transaction block. In the default mode, commands are committed |
| only when <code class="command">EXEC SQL COMMIT</code> is issued. |
| </p></dd><dt><span class="term"><code class="option">-v</code></span></dt><dd><p> |
| Print additional information including the version and the |
| "include" path. |
| </p></dd><dt><span class="term"><code class="option">--version</code></span></dt><dd><p> |
| Print the <span class="application">ecpg</span> version and exit. |
| </p></dd><dt><span class="term"><code class="option">-?</code><br /></span><span class="term"><code class="option">--help</code></span></dt><dd><p> |
| Show help about <span class="application">ecpg</span> command line |
| arguments, and exit. |
| </p></dd></dl></div><p> |
| </p></div><div class="refsect1" id="id-1.9.4.8.7"><h2>Notes</h2><p> |
| When compiling the preprocessed C code files, the compiler needs to |
| be able to find the <span class="application">ECPG</span> header files in the |
| <span class="productname">PostgreSQL</span> include directory. Therefore, you might |
| have to use the <code class="option">-I</code> option when invoking the compiler |
| (e.g., <code class="literal">-I/usr/local/pgsql/include</code>). |
| </p><p> |
| Programs using C code with embedded SQL have to be linked against |
| the <code class="filename">libecpg</code> library, for example using the |
| linker options <code class="literal">-L/usr/local/pgsql/lib -lecpg</code>. |
| </p><p> |
| The value of either of these directories that is appropriate for |
| the installation can be found out using <a class="xref" href="app-pgconfig.html" title="pg_config"><span class="refentrytitle"><span class="application">pg_config</span></span></a>. |
| </p></div><div class="refsect1" id="id-1.9.4.8.8"><h2>Examples</h2><p> |
| If you have an embedded SQL C source file named |
| <code class="filename">prog1.pgc</code>, you can create an executable |
| program using the following sequence of commands: |
| </p><pre class="programlisting"> |
| ecpg prog1.pgc |
| cc -I/usr/local/pgsql/include -c prog1.c |
| cc -o prog1 prog1.o -L/usr/local/pgsql/lib -lecpg |
| </pre></div></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="app-dropuser.html" title="dropuser">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="reference-client.html" title="PostgreSQL Client Applications">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="app-pgamcheck.html" title="pg_amcheck">Next</a></td></tr><tr><td width="40%" align="left" valign="top"><span class="application">dropuser</span> </td><td width="20%" align="center"><a accesskey="h" href="index.html" title="PostgreSQL 16.3 Documentation">Home</a></td><td width="40%" align="right" valign="top"> <span class="application">pg_amcheck</span></td></tr></table></div></body></html> |
