Header files included in your program

The Informix® ESQL/C preprocessor automatically includes the following Informix® ESQL/C header files in your program:

• The sqlhdr.h file provides cursor-related structures for your Informix® ESQL/C program.

  This header file automatically includes the sqlda.h and ifxtypes.h header files.

• The sqlca.h file, which allows your program to check the success or failure of your Informix® ESQL/C statements with the SQLSTATE or SQLCODE variable

To include any of the other header files in your Informix® ESQL/C program, you must use the include preprocessor directive. However, you only need to include the Informix® ESQL/C header file if your program refers to the structures or the definitions that the header file defines. For example, if your program accesses datetime data, you must include the datetime.h header file, as follows:

EXEC SQL include datetime.h;

Make sure to terminate the line of code with a semicolon. Some additional examples follow:

EXEC SQL include varchar.h;
EXEC SQL include sqlda;
$include sqlstype;