Tracing exceptions
Exception can be logged in a file when using the STARTLOG()
function.
Exceptions are automatically logged in a file, if all the following conditions are true:
- The STARTLOG function has been previously called to specify the name of the exception logging file.
 - The exception action is set to
CALL,GOTOorSTOP. Exceptions are not logged when the action isCONTINUEorRAISE. - The exception class is an 
ERROR,ANY ERRORorWARNING.NOT FOUNDexceptions cannot be logged. 
In other words, errors will not be logged in the case of WHENEVER { [ANY]
ERROR | WARNING } CONTINUE, or when controlled by a
TRY/CATCH block. 
Each log entry contains:
- The system-time
 - The location of the related instruction (source-file, line)
 - The error-number
 - The text of the error message, giving human-readable details for the exception