diff options
Diffstat (limited to 'doc/src')
| -rw-r--r-- | doc/src/sgml/xfunc.sgml | 50 |
1 files changed, 24 insertions, 26 deletions
diff --git a/doc/src/sgml/xfunc.sgml b/doc/src/sgml/xfunc.sgml index 1f03d7cd90b..b803ea2c9ee 100644 --- a/doc/src/sgml/xfunc.sgml +++ b/doc/src/sgml/xfunc.sgml @@ -1,4 +1,4 @@ -<!-- $PostgreSQL: pgsql/doc/src/sgml/xfunc.sgml,v 1.113 2006/05/30 14:09:32 momjian Exp $ --> +<!-- $PostgreSQL: pgsql/doc/src/sgml/xfunc.sgml,v 1.114 2006/05/30 21:21:29 tgl Exp $ --> <sect1 id="xfunc"> <title>User-Defined Functions</title> @@ -1149,13 +1149,6 @@ CREATE FUNCTION square_root(double precision) RETURNS double precision </para> <para> - After the module has been found, PostgreSQL looks for its magic block. - This block contains information about the environment a module was - compiled in. The server uses this to verify the module was compiled - under the same assumptions and environment as the backend. - </para> - - <para> The user ID the <productname>PostgreSQL</productname> server runs as must be able to traverse the path to the file you intend to load. Making the file or a higher-level directory not readable @@ -1960,31 +1953,36 @@ concat_text(PG_FUNCTION_ARGS) <listitem> <para> - To ensure your module is not loaded into an incompatible backend, it - is recommended to include a magic block. To do this you must include - the header <filename>pgmagic.h</filename> and declare the block as - follows: + Symbol names defined within object files must not conflict + with each other or with symbols defined in the + <productname>PostgreSQL</productname> server executable. You + will have to rename your functions or variables if you get + error messages to this effect. </para> + </listitem> -<programlisting> -#include "pgmagic.h" + <listitem> + <para> + To ensure your module is not loaded into an incompatible server, it + is recommended to include a <quote>magic block</>. This allows + the server to detect obvious incompatibilities, such as a module + compiled for a different major version of + <productname>PostgreSQL</productname>. It is likely that magic + blocks will be required in future releases. To include a magic + block, write this in one (and only one) of your module source files, + after having included the header <filename>fmgr.h</>: + </para> +<programlisting> +#ifdef PG_MODULE_MAGIC PG_MODULE_MAGIC; +#endif </programlisting> <para> - If the module consists of multiple source files, this only needs to - be done in one of them. - </para> - </listitem> - - <listitem> - <para> - Symbol names defined within object files must not conflict - with each other or with symbols defined in the - <productname>PostgreSQL</productname> server executable. You - will have to rename your functions or variables if you get - error messages to this effect. + The <literal>#ifdef</> test can be omitted if your code doesn't + need to compile against pre-8.2 <productname>PostgreSQL</productname> + releases. </para> </listitem> |