ECPG(1) PostgreSQL Client Applications ECPG(1)NAMEecpg - embedded SQL C preprocessor
SYNOPSISecpg [ option... ] file...
DESCRIPTIONecpg 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 func-
tion 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 pre-
ferrably have the extension .pgc, in which case the exten-
sion 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 overrid-
den using the -o option.
This reference page does not describe the embedded SQL
language. See the PostgreSQL Programmer's Guide for that.
OPTIONSecpg accepts the following command-line arguments:
-c Automatically generate C code from SQL code. Cur-
rently, this works for EXEC SQL TYPE.
-D symbol
Define a C preprocessor symbol.
-I directory
Specify an additional include path, used to find
files included via EXEC SQL INCLUDE. Defaults are .
(current directory), /usr/local/include, the Post-
greSQL include directory which is defined at com-
pile 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.
-t Turn on autocommit of transactions. In this mode,
each query is automatically committed unless it is
inside an explicit transaction block. In the
default mode, queries 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.
NOTES
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 flags
-L/usr/local/pgsql/lib -lecpg.
The value of either of these directories that is appropri-
ate for the installation can be found out using pg_con-
fig(1).
EXAMPLES
If you have an embedded SQL C source file named prog1.pgc,
you can create an executable program using the following
sequence of commands:
ecpg prog1.pgc
cc -I/usr/local/pgsql/include -c prog1.c
cc -o prog1 prog1.o -L/usr/local/pgsql/lib -lecpg
SEE ALSO
PostgreSQL Programmer's Guide for a more detailed descrip-
tion of the embedded SQL interface
Application 2002-11-22 ECPG(1)
