Records a user-defined data sample.
|Example: lr.user_data_point||Informational Functions|
|sample_name||The data point name.|
|value||The value to record.|
The lr.user_data_point function allows you to record your own data for analysis. Each time you want to record a point, use this function to record the sample name and the value. The time of the sample is recorded automatically. After the execution, you can use the User Defined Data Points graph to analyze the results.
The following prefixes in sample_name are reserved:
A data point with any of these prefixes, for example "HTTP_BT", will not appear on the graph. However, the prefixes are case-sensitive, therefore "http_BT" is a valid sample_name.
Returns 0 on success and -1 on failure.