Each of the scripts fetches events from a different web site and outputs the ics data on STDOUT, so you might want to pipe the output to a file.
Example:
```bash
$ perl website2ics.pl > calendarfile.ics
````
The only script that supports **and requires** command line arguments is `intro2ics.pl`. You have to give at least one city name for which events should be fetched.
Example:
```bash
$ perl intro2ics.pl hamburg berlin muenchen > calendarfile.ics