You can determine the value of a variable in the routine at the point of interrupt by using the compiled code listing as a guide to its address, then finding this address in the Language Environment dump. The method you use depends on the storage class of variable.
This method is generally used when no symbolic variables have been dumped (by using the TEST compiler option).
It is possible for the routine to be interrupted before the value of the variable is placed in the location provided for it. This can explain unexpected values in the dump.