For PL/I programs, you can configure the debugger to identify exceptions thrown during execution by setting one or more PL/I conditions, and by setting signal breakpoints. The debugger reports only the exceptions thrown for the conditions and signal breakpoints you specify.
You can filter for the following PL/I conditions:
Signal breakpoints are defined by the operating system. You can see a list of them on the PL/I Signal Breakpoints tab in the Visual Studio Outputs window.
When you continue debugging after hitting a breakpoint, the debugger pops up the Exception Thrown message box, which reports any exceptions thrown for the conditions you have set as the program executed up to the breakpoint.
For complete information about handling thrown exceptions as you debug, see the Manage exceptions with the debugger section in your Visual Studio documentation.