gtpc2mi9C/C++ Language Support User's Guide

TO2_class-Retrieve the User Class ID of the Collection

This function is used to retrieve the user class identifier (ID) as set by the TO2_setClass function. If the ID has not been set, a null string is returned to the field parameter.

Format

#include <c$to2.h>
long  TO2_class (const TO2_PID_PTR   pid_ptr,
                       TO2_ENV_PTR   env_ptr,
                       void         *field);

pid_ptr
The pointer to the persistent identifier (PID) of the collection.

env_ptr
The pointer to the environment as returned by the TO2_createEnv function.

field
The pointer to an area in which the 32-byte class ID value will be returned.

Normal Return

The normal return is a positive value.

Error Return

An error return is indicated by a zero return code. When zero is returned, use the TO2_getErrorCode function to determine the specific error code. For more information, see Error Handling.

The following error codes are common for this function:

TO2_ERROR_ENV

TO2_ERROR_PID

Programming Considerations

A commit scope will be created for the TO2_class request. If the request is successful, the scope will be committed. If an error occurs while processing the TO2_class request, the scope will be rolled back.

Examples

The following example retrieves the user class ID value set for a collection.

#include <c$to2.h>                /* Needed for TO2 API functions      */
#include <stdio.h>                /* APIs for standard I/O functions   */
 
TO2_ENV_PTR      env_ptr;         /* Pointer to TO2 Environment        */
TO2_PID          blob;
char classID[32] = "                                ";

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if (TO2_class(&blob, env_ptr, classID) == TO2_ERROR) { printf("TO2_class failed!\n"); process_error(env_ptr); } else { printf("TO2_class successful!\n"); printf("User Class ID value is - %s \n",classID); }
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if (memcmp("LOG", returned_value, 4))

Related Information

TO2_setClass-Set the User Class ID of the Collection.