gtpc2me5C/C++ Language Support User's Guide

TO2_getMaxKeyLength-Retrieve the Maximum Key Length Value

This function returns the maximum key length value that was set when you created the collection.

Note:
This function does not support all collections. See Table 47 for collections that are supported for this function.

Format

#include <c$to2.h>
long  TO2_getMaxKeyLength (const TO2_PID_PTR   pid_ptr,
                                 TO2_ENV_PTR   env_ptr);

pid_ptr
The pointer to the persistent identifier (PID) assigned to the collection that will be interrogated.

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

Normal Return

The maximum key length will be returned as the return value.

Error Return

An error return is indicated by a zero. 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_METHOD

TO2_ERROR_PID

TO2_ERROR_ZERO_PID

Programming Considerations

This function does not use TPF transaction services on behalf of the caller.

Examples

The following example prints the maximum key length.

#include <c$to2.h>          /* Needed for TO2 API functions    */
#include <stdio.h>          /* APIs for standard I/O functions */
 
TO2_ENV_PTR    env_ptr;     /* PTR to the TO2 environment      */
TO2_PID        collect;     /* PID return field                */
long           max;         /* Maximum key length              */

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if (((max = TO2_getMaxKeyLength(&collect, env_ptr)) == TO2_ERROR) { printf("TO2_getMaxKeyLength failed!\n"); process_error(env_ptr); } else { printf("Maximum key length is %d.\n", max); }

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