This first code example defines an error handler function called
my_error_handler. After       connecting to the database, a 
SELECT statements
tries to fetch a row from a       table that does not exist, and raises
SQL error -217 when connected to Informix
®:
MAIN
  WHENEVER ERROR CALL my_error_handler
  DATABASE stores 
  SELECT dummy FROM systables WHERE tabid=1
END MAIN
FUNCTION my_error_handler()
  DISPLAY "Error:", STATUS
  EXIT PROGRAM 1
END FUNCTION
 
Program output:
Error:      -217