4.1 Action Functions

Action functions enable your DTrace programs to interact with the system outside of DTrace. The most common actions record data to a DTrace buffer. Other actions are available, such as stopping the current process, raising a specific signal on the current process, and ceasing tracing altogether. Some of these actions are destructive, in that they change the system, albeit in a well-defined way. These actions may only be used if destructive actions have been explicitly enabled. By default, data recording actions record data to the principal buffer. For more information about the principal buffer and buffer policies, see Chapter 5, Buffers and Buffering.