Utility Functions and C Language Reference > Utility Functions: C Language (lr_) > Alphabetical Listing > lr_user_data_point_instance_ex


Records a user-defined data sample and correlates it to a transaction instance.

C Language

long lr_user_data_point_instance_ex( const char* sample_name, double value, long transaction_handle, int log_flag );
Example: lr_user_data_point_instance_ex Informational Functions


Name Comments
sample_name The data point name.
value The value to record.
parent_handle A transaction instance identifier with which to associate the data_point.
log_flag Determines whether the data point should be logged or not: DP_FLAGS_NO_LOG (1) DP_FLAGS_STANDARD_LOG DP_FLAGS_EXTENDED_LOG (3)

The lr_user_data_point_instance_ex function is the same as lr_user_data_point_instance except for the additional parameter log_flag.

Logging means writing data to a file. lr_user_data_point_instance_ex enables you to write a data point to the Vuser log file. When run in VuGen, the output is output.txt

You may want to write the data point conditionally according to the importance of the data to be logged. It can either be part of a Standard level when only the most important information is logged or an Extended level, when fuller logging is required.

log_flag denotes the log level and correlates to the settings found in VuGen's Log runtime setting which specifies how the script handles logging to a file during script execution. If DP_FLAGS_EXTENDED_LOG is passed to lr_user_data_point_instance_ex then the data point is logged only when the Extended runtime Log setting is activate. If log_flag is DP_FLAGS_STANDARD_LOG then it will be logged only if the Standard setting is active. DP_FLAGS_NO_LOG indicates that this data point is never written to a log file.

Caution: If there are too many unique data point names, the Controller may run out of memory. This can happen, for example, when the data point name is created with code or by using parameter evaluation, and a unique name is created each iteration.

The result during test run is a large number of graphs, each with a single data point. In a long test, these graphs can consume all available memory.

Return Values

This function returns 0 if it succeeds, and -1 if it fails to write the sampled data.


All string arguments (char type) can be parameterized using standard parameterization.