Informix libraries

These topics describe how to link the static, shared, and thread-safe HCL Informix® general libraries with your Informix ESQL/C application.

HCL Informix products use the Informix general libraries for interactions between the client SQL application programming interface (API) products (Informix ESQL/C) and the database server. You can choose between the following types of Informix general libraries to link with your Informix ESQL/C application:

Static Informix general libraries
To link a static library, the linker copies the library functions to the executable file of your Informix ESQL/C program. The static Informix general libraries allow the Informix ESQL/C program on computers that do not support shared memory to access the Informix general library functions.
Shared Informix general libraries
To link a shared library, the linker copies information about the location of the library to the executable file of your Informix ESQL/C program. The shared Informix libraries allow several applications to share a single copy of these libraries, which the operating system loads, once, into shared memory.
Thread-safe versions of static and shared Informix general libraries
The thread-safe versions of Informix general libraries allow the Informix ESQL/C application that has several threads to call these library functions simultaneously. The thread-safe versions of Informix libraries are available as both static libraries and shared libraries.

Beginning with HCL Informix Client Software Development Kit version 3.0, static versions of Informix general libraries are available on Windows and UNIX operating systems. The following table shows the available options.

Table 1. Different version of the ESQL/C general library available for UNIX and Windows
Linking options	Thread-safe	Default
Static	Static, thread-safe general libraries	Static, default general libraries
Shared	Shared, thread-safe general libraries	Shared, default general libraries.