unwind the stack การใช้

• Common Lisp calls the exception handler and does not unwind the stack.
• C's setjmp / longjmp are also equivalent : they can only be used to unwind the stack.
• When an exception is thrown, the kernel and base libraries unwind the stack running handlers and filters as they are encountered.
• So instead of simply exiting with an error, the function may " establish restarts " offering various ways to continue for instance, to skip the log entry, to supply default or null values for the unreadable fields, to ask the user for the missing values, " or " to unwind the stack and abort processing with an error message.