20 OCI Cartridge Functions

This chapter presents the cartridge functions. For code examples, see the demonstration programs included with your Oracle Database installation. For additional information, see Appendix B.

This chapter contains these topics:

• Introduction to External Procedure and Cartridge Services Functions

• Cartridge Services — OCI External Procedures

• Cartridge Services — Memory Services

• Cartridge Services — Maintaining Context

• Cartridge Services — Parameter Manager Interface

• Cartridge Services — File I/O Interface

• Cartridge Services — String Formatting Interface

Introduction to External Procedure and Cartridge Services Functions

This chapter first describes the OCI external procedure functions. These functions enable users of external procedures to raise errors, allocate some memory, and get OCI context information. For more information about using these functions in external procedures, see the Oracle Database Advanced Application Developer's Guide.

Then the cartridge services functions are described. For more information about using these functions, see Oracle Database Data Cartridge Developer's Guide.

Conventions for OCI Functions

For each function, the following information is listed:

Purpose

A brief description of the action performed by the function.

Syntax

The function declaration.

Parameters

A description of each of the function's parameters. This includes the parameter's mode. The mode of a parameter has three possible values, as described in Table 20-1.

Table 20-1 Mode of a Parameter

Mode	Description
IN	A parameter that passes data to the OCI
OUT	A parameter that receives data from the OCI on this call
IN/OUT	A parameter that passes data on the call and receives data on the return from this or a subsequent call

Comments

More detailed information about the function (if available). This may include restrictions on the use of the function, or other information that might be useful when using the function in an application.

Returns

A list of possible return values for the function.

Related Functions

A list of related function calls. For cartridge services, see all the other functions in the group being documented.

Return Codes

Success and error return codes are defined for certain external procedure interface functions. If a particular interface function returns OCIEXTPROC_SUCCESS or OCIEXTPROC_ERROR, then applications must use these macros to check for return values.

• OCIEXTPROC_SUCCESS - External Procedure Success Return Code

• OCIEXTPROC_ERROR - External Procedure Failure Return Code

With_Context Type

The C callable interface to PL/SQL external procedures requires the with_context parameter to be passed. The type of this structure is OCIExtProcContext, which is opaque to the user.

The user can declare the with_context parameter in the application as follows:

OCIExtProcContext *with_context;