ecpg — embedded SQL C preprocessor
ecpg
[option
...] file
...
ecpg
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.
ecpg
will convert each input file given on the
command line to the corresponding C output file. Input files
preferably have the extension .pgc
, in which
case the extension will be replaced by .c
to
determine the output file name. If the extension of the input file
is not .pgc
, then the output file name is
computed by appending .c
to the full file name.
The output file name can also be overridden using the
-o
option.
This reference page does not describe the embedded SQL language. See Chapter 31, ECPG - Embedded SQL in C for more information on that topic.
ecpg
accepts the following command-line
arguments:
-c
Automatically generate certain C code from SQL code. Currently, this
works for EXEC SQL TYPE
.
-C mode
Set a compatibility mode. mode
may
be INFORMIX
or
INFORMIX_SE
.
-D symbol
Define a C preprocessor symbol.
-i
Parse system include files as well.
-I directory
Specify an additional include path, used to find files included
via EXEC SQL INCLUDE
. Defaults are
.
(current directory),
/usr/local/include
, the
PostgreSQL include directory which
is defined at compile time (default:
/usr/local/pgsql/include
), and
/usr/include
, in that order.
-o filename
Specifies that ecpg
should write all
its output to the given filename
.
-r option
Selects a run-time behavior. Currently,
option
can only be
no_indicator
.
-t
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 EXEC SQL COMMIT
is issued.
-v
Print additional information including the version and the include path.
--help
Show a brief summary of the command usage, then exit.
--version
Output version information, then exit.
When compiling the preprocessed C code files, the compiler needs to
be able to find the ECPG header files in the
PostgreSQL include directory. Therefore, one might
have to use the -I
option when invoking the compiler
(e.g., -I/usr/local/pgsql/include
).
Programs using C code with embedded SQL have to be linked against
the libecpg
library, for example using the
linker options -L/usr/local/pgsql/lib -lecpg
.
The value of either of these directories that is appropriate for the installation can be found out using pg_config.