Several initialization and termination routines are called to allow the user to predefine values, to open files, or to book histograms. None of these subroutines take an argument. In the following each routine is described.
disinit is called only once at the beginning of the program. This is the place to initialize the users steering card values.
After the steering card has been read init is called. Here the parameter values can be copied to a common block, as proposed at the end of section 2. Also output files should be opened here.
Corresponding to these initialization routines a termination routine disterm exists. This function is called once at the end of the run. Here all files should be closed.
In addition to these called-once routines an additional set of init and term routines exists. The evtinit subroutine is called before a new event is generated and evtterm afterwards. Since all contributions to the observable of one event have to be added before the error can be calculated [4], the main summation can only be done in those routines. Please note that the evtterm routine will not be called if an event has to be dropped due to technical reasons (e.g. after a floating point exception). See the web version[5] for an example.