IKJEFXG1 receives control whenever TSO/E is obtaining a line of input from the input stack, the REXX data stack, or the terminal through the PUTGET or GETLINE service routine. Recursive calls are possible if the exit attempts to invoke the PUTGET or GETLINE service routine or any program (for example, the parse service routine) that invokes PUTGET or GETLINE.

The exit must be reentrant, refreshable, reusable, and reside in an APF-authorized library. It is inadvisable for the exit to have APF authorization unless it is designed also to be called as the entry point for a job step program.