| Pro*C/C++ Getting Started 10g Release 2 (10.2) for Microsoft Windows (32-Bit) Part Number B14321-01 |
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| Pro*C/C++ Getting Started 10g Release 2 (10.2) for Microsoft Windows (32-Bit) Part Number B14321-01 |
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View PDF |
This chapter explains how to create and precompile a project. It also explains how to use Pro*C/C++ at the command prompt.
This chapter contains these topics:
Using Pro*C/C++ with the Oracle XA Library
See Also:
Pro*C/C++ Programmer's Guide for additional informationTo precompile a file at the command prompt, enter the following command:
C:\> proc iname=filename.pc
where filename.pc is the name of the file. If the file is not in your current working directory, include the file's full path after the INAME argument.
Pro*C/C++ generates filename.c, which can be compiled by your C compiler.
The ORACLE_BASE\ORACLE_HOME\precomp\public directory contains the Pro*C/C++ header files. Table 2-1 lists and describes the header files.
Table 2-1 Header Files
| Header Files | Description |
|---|---|
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Contains the Oracle Communications Area (ORACA), which helps you to diagnose runtime errors and to monitor your program's use of various Oracle Database 10g resources. |
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Contains SQLLIB functions that enable the Oracle Call Interface (OCI) environment handle and OCI service context to be obtained in a Pro*C/C++ application. |
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Contains ANSI prototypes for externalized functions that can be used in conjunction with OCI. |
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Contains the SQL Communications Area (SQLCA), which helps you to diagnose runtime errors. The SQLCA is updated after every executable SQL statement. |
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Contains platform-specific ANSI prototypes for SQLLIB functions that are generated by Pro*C/C++. By default, Pro*C/C++ does not support full-function prototyping of SQL programming calls. If you need this feature, include |
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Contains the Oracle Communications Area (ORACA), which helps you to diagnose runtime errors and to monitor your program's use of various Oracle Database 10g resources. |
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Contains SQLLIB functions that enable the Oracle Call Interface (OCI) environment handle and OCI service context to be obtained in a Pro*C/C++ application. |
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Contains ANSI prototypes for externalized functions that can be used in conjunction with OCI. |
The ORACLE_BASE\ORACLE_HOME\precomp\lib\msvc directory contains the library file that you use when linking Pro*C/C++ applications. The library file is called orasql110.lib.
Pro*C/C++ application program interface (API) calls are implemented in DLL files provided with your Pro*C/C++ software. To use the DLLs, you must link your application with the import libraries (.lib files) that correspond to the Pro*C/C++ DLLs. Also, you must ensure that the DLL files are installed on the computer that is running your Pro*C/C++ application.
Microsoft provides you with three libraries: libc.lib, libcmt.lib, and msvcrt.lib. The Oracle DLLs use the msvcrt.lib runtime library. You must link with msvcrt.lib rather than the other two Microsoft libraries.
Build multithreaded applications if you are planning to perform concurrent database operations.
Windows 2000, and Windows 98 schedule and allocate threads belonging to processes. A thread is a path of a program's execution. It consists of a kernel stack, the state of the CPU registers, a thread environment block, and a users stack. Each thread shares the resources of a process. Multithreaded applications use the resources of a process to coordinate the activities of individual threads.
When building a multithreaded application, make sure that your C/C++ code is reentrant. This means that access to static or global data must be restricted to one thread at a time. If you mix multithreaded and non-reentrant functions, one thread can modify information that is required by another thread.
The Pro*C/C++ precompiler automatically creates variables on the local stack of the thread. This ensures that each thread using the Pro*C/C++ function has access to a unique set of variables and is reentrant.
See Also:
Pro*C/C++ Programmer's Guidefor additional information on how to write multithreaded applications with Pro*C/C++This section highlights issues related to Pro*C/C++ for Windows platforms.
See Also:
"Precompiler Options" of Pro*C/C++ Programmer's GuideA configuration file is a text file that contains precompiler options.
For this release, the system configuration file is called pcscfg.cfg. This file is located in the ORACLE_BASE\ORACLE_HOME\precomp\admin directory.
The CODE option has a default setting of ANSI_C. Pro*C/C++ for other operating systems may have a default setting of KR_C.
For sample programs that precompile with PARSE=PARTIAL or PARSE=FULL, an include path of c:\program files\devstudio\vc\include has been added. If Microsoft Visual C++ has been installed in a different location, modify the Include Directories field accordingly for the sample programs to precompile correctly.
The XA Application Program Interface (API) is typically used to enable an Oracle database to interact with a Transaction Processing (TP) monitor, such as:
BEA Tuxedo
IBM Transarc Encina
IBM CICS
You can also use TP monitor statements in your client programs. The use of the XA API is also supported from both Pro*C/C++ and OCI.
The Oracle XA Library is automatically installed as part of Oracle Database 10g Enterprise Edition. The following components are created in your Oracle home directory:
Table 2-2 Oracle XA Library Components and Locations
| Component | Location |
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To compile and link a Pro*C/C++ program with XA:
Precompile filename.pc using Pro*C/C++ to generate filename.c.
Compile filename.c, making sure to include ORACLE_BASE\ORACLE_HOME\rdbms\xa in your path.
Link filename.obj with the following libraries:
| Library | Location |
|---|---|
oraxa10.lib |
ORACLE_BASE\ORACLE_HOME\rdbms\xa |
oci.lib |
ORACLE_BASE\ORACLE_HOME\oci\lib\msvc |
orasql10.lib |
ORACLE_BASE\ORACLE_HOME\precomp\lib\msvc |
Run filename.exe.
Oracle supports the use of XA dynamic registration. XA dynamic registration improves the performance of applications that interface with XA-compliant TP monitors.
For TP monitors to use XA dynamic registration with an Oracle database, you must add either an environmental variable or a registry variable to the Windows computer on which your TP monitor is running. See either of the following sections for instructions:
Adding an environmental variable at the command prompt affects only the current session.
To add an environmental variable for the current session:
Go to the computer where your TP monitor is installed.
Enter the following at the command prompt:
C:\> set ORA_XA_REG_DLL = vendor.dll
where vendor.dll is the TP monitor DLL provided by your vendor.
Adding a registry variable affects all sessions on your Windows computer. This is useful for computers where only one TP monitor is running.
To add a registry variable for all sessions:
Go to the computer where your TP monitor is installed.
Enter the following at the command prompt:
C:\> regedt32
The Registry Editor window appears.
Go to HKEY_LOCAL_MACHINE\SOFTWARE\ORACLE\HOMEID.
Select the Add Value option in the Edit menu.
The Add Value dialog box appears.
Enter ORA_XA_REG_DLL in the Value Name field.
Select REG_EXPAND_SZ from the Data Type list .
Click OK.
The String Editor dialog appears.
Enter vendor.dll in the String field, where vendor.dll is the TP monitor DLL provided by your vendor.
Click OK.
The Registry Editor adds the parameter.
Select Exit from the Registry menu.
The registry exits.
Refer to the following for more information about XA and TP monitors:
Distributed TP: The XA Specification (C193) published by the Open Group. See the Web site at:
http://www.opengroup.org/publications/catalog/tp.htm
The Open Group., 1010 El Camino Real, Suite 380, Menlo Park, CA 94025, U.S.A.
Your specific TP monitor documentation
See Also:
Oracle Database Application Developer's Guide - Fundamentalsfor more information about the Oracle XA Library and using XA dynamic registration