thinkRF provides many APIs to facilitate the capturing of data, along with processing.

In general, thinkRF's RTSA device sends I/Q data packets to the host along with associated context packets using the standard VRT protocol, please refer to your product's Programmer's Guide (R55x0 Programmer's Guide or R57x0 Programmer's Guide) for this protocol.  Additionally, refer to the product's User Guide and the Programmer's Guide for how to connect and capture data.  This article would be a useful read also: AppNote: Performing Real Time Data Acquisition With ... R5xx0

If you are looking to save the acquired data, you could either use the "Save Data" feature of thinkRF's S240v5 GUI application or write your own code (refer to this article