Warning of Trace Data Lost
Original Publication Date: 1986-Mar-01
Included in the Prior Art Database: 2005-Mar-08
A method to inform the operator of an IBM PC Network SNA 3270 Emulation Program that trace data may have been lost is described. The IBM PC Network SNA 3270 Emulation (PCN 3270) Program provides an online data trace function to trace SNA data. The trace function makes use of two buffers, buffer A and buffer B. The trace process starts with buffer A, filling it with trace data. When buffer A is full, the trace process switches to using buffer B, and initiates writing of buffer A to disk. It is possible that trace data may arrive at a time when buffer B is full, and buffer A is still waiting to be written to disk. In this case, the arriving trace data is discarded, and a way of notifying the operator of data lost is needed. For each record of SNA data that is stored in the trace buffers, a trace header byte is stored.