Previously, we discussed how to add the basic APRE library in the "How to make a basic Makefile" chapter. This chapter describes the library and compile options that must be additionally described in Makefile in the environment in which the AIX xlc compiler is used.

Library and compile options for APRE compile in AIX environment

Library to be added to Makefile

As previously explained, the basic APRE library "-lapr -lodbccli" should be described in Makefile.

When compiling only with the basic library added, there are system libraries referenced by the APRE library and a reference error occurs. Therefore, system libraries used in APRE must be specified in Makefile as follows.

Compile Options

It is necessary to specify the following options to improve performance and specify the compile bit type.

Example of simple Makefile

The simplest Makefile that can compile ARE in AIX xlc environment is completed as follows. In addition, if there is an additional library referenced by the program, the library must be additionally described in Makefile.

Example of Makefile for 32-bit compile

An example of Makefile for 32bit compile is as follows. Specify "-q32" as a compile option, and specify the path where 32bit APRE library is installed in the path referencing the Header file and Library. In addition, the APRE Precompiler also specifies the path to execute 32bit APRE. If necessary, increase the memory segment to be used in the program, such as "-bmaxdata:0x80000000". In case of "bmaxdata:0x80000000", it can be used up to 2G.

Example of Makefile using APRE Shared Library(libapre_sl.so)

In $ALTIBASE_HOME/library, there are liapre_sl.so and libodbccli_sl.so provided in the form of shared library in addition to libapre.a, which is a static library.

Using a shared library has the following advantages compared to using a static library:

• Can reduce the size of the executable file.
• After loading the library into memory, it can be shared, reducing the memory usage of the program
• When the used library is changed, only the library needs to be replaced and there is no need to recompile the executable file.

The following is an example of Makefile using a shared library using the xlc compiler in AIX. To use runtime linking, "brtl" was added as a link option and APRE shared library was added as a library.

Example of Makefile for Shared library build using APRE source

If necessary, there is a case that a shared library consisting of a function that searches DB with APRE must be created and used by calling it from a program. The example below is an example of Makefile for creating a shared library with APRE.

/* connect1.sc */
int contest_db();
int contest_db()
{
    /* declare host variables */
    EXEC SQL BEGIN DECLARE SECTION;
    char usr[10];
    char pwd[10];
    char conn_opt1[100];
    char conn_opt2[100];
    char conn_opt3[100];
    EXEC SQL END DECLARE SECTION;
    .................
    EXEC SQL CONNECT :usr IDENTIFIED BY :pwd USING :conn_opt3;
    ....
}

/* alticonn.h */
 int contest_db();

 /* test.c */
#include "alticonn.h"
extern int contest_db();
int main()
{
  contest_db();
}