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diff --git a/doc/src/sgml/ref/ecpg-ref.sgml b/doc/src/sgml/ref/ecpg-ref.sgml new file mode 100644 index 0000000..f3b6034 --- /dev/null +++ b/doc/src/sgml/ref/ecpg-ref.sgml @@ -0,0 +1,278 @@ +<!-- +doc/src/sgml/ref/ecpg-ref.sgml +PostgreSQL documentation +--> + +<refentry id="app-ecpg"> + <indexterm zone="app-ecpg"> + <primary>ecpg</primary> + </indexterm> + + <refmeta> + <refentrytitle><application>ecpg</application></refentrytitle> + <manvolnum>1</manvolnum> + <refmiscinfo>Application</refmiscinfo> + </refmeta> + + <refnamediv> + <refname><application>ecpg</application></refname> + <refpurpose>embedded SQL C preprocessor</refpurpose> + </refnamediv> + + <refsynopsisdiv> + <cmdsynopsis> + <command>ecpg</command> + <arg choice="opt" rep="repeat"><replaceable>option</replaceable></arg> + <arg choice="plain" rep="repeat"><replaceable>file</replaceable></arg> + </cmdsynopsis> + </refsynopsisdiv> + + + <refsect1 id="app-ecpg-description"> + <title>Description</title> + + <para> + <command>ecpg</command> 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. + </para> + + <para> + <command>ecpg</command> 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, <filename>.pgc</filename> is + assumed. The file's extension will be replaced + by <filename>.c</filename> to construct the output file name. + But the output file name can be overridden using the + <option>-o</option> option. + </para> + + <para> + If an input file name is just <literal>-</literal>, + <command>ecpg</command> reads the program from standard input + (and writes to standard output, unless that is overridden + with <option>-o</option>). + </para> + + <para> + This reference page does not describe the embedded SQL language. + See <xref linkend="ecpg"/> for more information on that topic. + </para> + </refsect1> + + + <refsect1> + <title>Options</title> + + <para> + <command>ecpg</command> accepts the following command-line + arguments: + + <variablelist> + <varlistentry> + <term><option>-c</option></term> + <listitem> + <para> + Automatically generate certain C code from SQL code. Currently, this + works for <literal>EXEC SQL TYPE</literal>. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term><option>-C <replaceable>mode</replaceable></option></term> + <listitem> + <para> + Set a compatibility mode. <replaceable>mode</replaceable> can + be <literal>INFORMIX</literal>, + <literal>INFORMIX_SE</literal>, or <literal>ORACLE</literal>. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term><option>-D <replaceable>symbol</replaceable></option></term> + <listitem> + <para> + Define a C preprocessor symbol. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term><option>-h</option></term> + <listitem> + <para> + Process header files. When this option is specified, the output file + extension becomes <literal>.h</literal> not <literal>.c</literal>, + and the default input file extension is <literal>.pgh</literal> + not <literal>.pgc</literal>. Also, the <option>-c</option> option is + forced on. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term><option>-i</option></term> + <listitem> + <para> + Parse system include files as well. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term><option>-I <replaceable class="parameter">directory</replaceable></option></term> + <listitem> + <para> + Specify an additional include path, used to find files included + via <literal>EXEC SQL INCLUDE</literal>. Defaults are + <filename>.</filename> (current directory), + <filename>/usr/local/include</filename>, the + <productname>PostgreSQL</productname> include directory which + is defined at compile time (default: + <filename>/usr/local/pgsql/include</filename>), and + <filename>/usr/include</filename>, in that order. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term><option>-o <replaceable>filename</replaceable></option></term> + <listitem> + <para> + Specifies that <command>ecpg</command> should write all + its output to the given <replaceable>filename</replaceable>. + Write <literal>-o -</literal> to send all output to standard output. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term><option>-r <replaceable>option</replaceable></option></term> + <listitem> + <para> + Selects run-time behavior. <replaceable>Option</replaceable> can be + one of the following: + <variablelist> + <varlistentry> + <term><option>no_indicator</option></term> + <listitem> + <para> + Do not use indicators but instead use special values to represent + null values. Historically there have been databases using this approach. + </para> + </listitem> + </varlistentry> + <varlistentry> + <term><option>prepare</option></term> + <listitem> + <para> + 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. + </para> + </listitem> + </varlistentry> + <varlistentry> + <term><option>questionmarks</option></term> + <listitem> + <para> + Allow question mark as placeholder for compatibility reasons. + This used to be the default long ago. + </para> + </listitem> + </varlistentry> + </variablelist></para> + </listitem> + </varlistentry> + + <varlistentry> + <term><option>-t</option></term> + <listitem> + <para> + 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 <command>EXEC SQL COMMIT</command> is issued. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term><option>-v</option></term> + <listitem> + <para> + Print additional information including the version and the + "include" path. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term><option>--version</option></term> + <listitem> + <para> + Print the <application>ecpg</application> version and exit. + </para> + </listitem> + </varlistentry> + + <varlistentry> + <term><option>-?</option></term> + <term><option>--help</option></term> + <listitem> + <para> + Show help about <application>ecpg</application> command line + arguments, and exit. + </para> + </listitem> + </varlistentry> + + </variablelist> + </para> + </refsect1> + + + <refsect1> + <title>Notes</title> + + <para> + When compiling the preprocessed C code files, the compiler needs to + be able to find the <application>ECPG</application> header files in the + <productname>PostgreSQL</productname> include directory. Therefore, you might + have to use the <option>-I</option> option when invoking the compiler + (e.g., <literal>-I/usr/local/pgsql/include</literal>). + </para> + + <para> + Programs using C code with embedded SQL have to be linked against + the <filename>libecpg</filename> library, for example using the + linker options <literal>-L/usr/local/pgsql/lib -lecpg</literal>. + </para> + + <para> + The value of either of these directories that is appropriate for + the installation can be found out using <xref + linkend="app-pgconfig"/>. + </para> + </refsect1> + + + <refsect1> + <title>Examples</title> + + <para> + If you have an embedded SQL C source file named + <filename>prog1.pgc</filename>, you can create an executable + program using the following sequence of commands: +<programlisting> +ecpg prog1.pgc +cc -I/usr/local/pgsql/include -c prog1.c +cc -o prog1 prog1.o -L/usr/local/pgsql/lib -lecpg +</programlisting></para> + </refsect1> + +</refentry> |