Using the command line interface of debug

Change command

The change command allows you to alter an event definition without deleting the event and creating a new one. The only aspect of an event definition you can't change is the type of event. You can't change a stop event into a system call event, but you can change the stop-expression in a stop event. The first argument to
change is the number of the event you are altering. The rest of the syntax depends on the type of each event:

   (stop events)	change event-number [options] [stop-expression] [{commands}]
   (system call events)	change event-number [options] [system call...] [{commands}]
   (signal events)	change event-number [options] [signal...] [{commands}]
   (onstop events)	change event-number [options] [{commands}]
   (exception events)	change event-number [options] [throw|catch] [exception-type][{commands}]

For example, if you had already defined a stop event with a complex command list, you could add another breakpoint without having to re-enter the command list. Here are some examples of using change:

   debug> change 1 -q           # make the event quiet
   debug> change 1 -v           # make it verbose again
   debug> change 1 {}           # remove the command list
   debug> change 1 -p all -c 2  # change the process list and count