RET_STK  is a small sbasic extension by Wolfgang Lenerz to get the value on the SMSQ/E SBasic return stack. This was written in response to a help request from a user on the ql-users mailing list, who wanted help to find a method in SBASIC to find which line number called a procedure in his program, to aid debugging. The extension may be downloaded from Wolfgang’s Qlstuff website at http://www.wlenerz.com/qlstuff/