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Introducing the Oracle Call Interface

This chapter provides introductory information to help you get started with the Oracle Call Interface for Windows NT and Windows 95/98.

Specific topics discussed are:

• What Is the Oracle Call Interface?
• What Is Included in the OCI Package?
• Oracle Directory Structure
• Sample Program for Windows NT and Windows 95/98
• Additional Information

What Is the Oracle Call Interface?

Oracle Call Interface (OCI) is an application programming interface (API) that allows applications written in C to interact with one or more Oracle servers. One of the main functions of an OCI program is to communicate with a database through an Oracle server.

The OCI gives your programs the capability to perform the full range of database operations that are possible with an Oracle8 server, including SQL statement processing and object manipulation.

Release 8.1 New Features

The Oracle8 OCI includes many new functions and performance enhancements that extend the capabilities of the OCI to handle objects in an Oracle8 server. (To use object functionality, you must have Oracle8 Enterprise Edition and the Objects option).

For Windows NT and Windows 95/98, Oracle8 OCI includes support for applications written with earlier releases ( 7.x/8.x) of OCI. Oracle has now removed any version number from the library name OCI. LIB.

What Is Included in the OCI Package?

The Oracle Call Interface for Windows NT and Windows 95/98 package includes:

• Oracle Call Interface
• Required Support Files (RSFs)
• Oracle Universal Installer
• Header files for compiling OCI applications
• Library files for linking OCI applications
• Sample programs for demonstrating how to build OCI applications

The Oracle Call Interface for Windows NT and Windows 95/98 package includes the additional libraries required for linking your OCI programs on Windows NT and Windows 95/98.

Oracle Directory Structure

When you install Oracle Call Interface for Windows NT and Windows 95/98, the Oracle Universal Installer creates an Oracle home directory on the hard drive of your computer. The default Oracle home directory is C:\ORACLE\ORA81, where C:\ORACLE is your top-level ORACLE_BASE directory, and ORA81 is your first Oracle home directory.

The OCI files are located in the Oracle home directory, as are the library files needed to link and run OCI applications and link with other Oracle for Windows NT products, such as Oracle Forms.

The Oracle home directory contains the following sub-directories that are relevant to OCI:

Directory Name	Contents
\BIN	Executables and help files
\OCI	Oracle Call Interface files.  \OCI contains the following subdirectories:
\INCLUDE	Header files, such as OCIDFN.H and OCIAPR.H
\LIB	Library files, for Microsoft, that link into OCI applications
\SAMPLES	Sample programs for Microsoft
\PRECOMP\ADMIN\OTT	Object Type Translator utility and default configuration file, OTTCFG.CFG

Sample Program for Windows NT and Windows 95/98

Oracle Universal Installer copies a set of sample programs and their corresponding project files into the \SAMPLES subdirectory. Oracle recommends that you build and run these sample programs to verify that OCI has been successfully installed and to familiarize yourself with the steps involved in developing OCI applications.

To build a sample program, run a batch file (MAKE.BAT) at the MS-DOS command prompt. For example, to build the CDEMO1.C sample, enter the following command from the SAMPLES directory:

MAKE CDEMO1

CDEMOMT.C is the only sample OCI application specific to Windows NT and Windows 95/98. The program demonstrates OCI multithreading (the thread safety feature of Oracle8 is also included on the Windows NT and Windows 95/98 platforms). It requires the EMP table from the default database.

This sample program spawns two simultaneous threads that attempt to insert different employee names with the same ID numbers. Thread synchronization is demonstrated.

Additional Information

For more information, see the following document included in your generic documentation set:

For information on...	See...
Using OCI  Function descriptions Oracle8 OCI's new features Multithreading	Oracle Call Interface Programmer's Guide