Managing Add-Ons

The BeOS, while not multi-user today, is an operating system designed with the idea that more than one user may want to use the same system. While not all of the pieces are in place, Be has tried to make sure that we think about multi-user access in each design decision we make, and at least not make things hard later.

An example of this is how the BeOS handles add-ons, small pieces of code that extend existing functionality in new ways. There are currently two places to store add-ons, one for the BeOS's built-in add-ons, and one for your own extra add-ons:

BeOS add-ons (reserved for use by Be): /beos/system/add-ons/
User add-ons (no restrictions): /home/config/add-ons/

Within the add-ons directory, add-ons are categorized into different subfolders, depending on what part of the BeOS they extend. This includes graphics drivers (which go in the app_server subdirectory), add-ons for the BeOS system itself (generally put into the "kernel" subdirectory, itself divided into further subdirectories), the Tracker, or third-party applications for applications like MailIt or Blanket.

In the BeOS, add-ons that a user installs into their add-on folder will "override," or take precedence, over add-ons that are provided with the BeOS. Usually this is what you want, as it allows each user (in a future multi-user version of the BeOS) to have their own suite of add-ons (which may override built-in BeOS functionality), while giving everyone access to basic functionality. However, sometimes this is not what you want.

For example, with the release of BeOS Release 3.1, Be is now providing an add-on for read-only access to FAT 16 and FAT 32 file systems, typically used by DOS and Windows (all flavors except Windows NT). This file system add-on goes into the /beos/system/add-ons/kernel/file_systems/ directory. But, if you've installed the DOSfs file system add-on, which previously was the only way to get access to these same Windows partitions, you've got it installed in /home/config/add-ons/kernel/file_systems/, and that will cause the DOSfs add-on to be used instead of the Be-provided add-on.

This is probably the opposite of what you want in this case, because the author of DOSfs is not planning to update that add-on, now that Be is providing similar functionality. And Be's version of this add-on will be fully supported by Be, including adding read/write access in the next release of the BeOS. So you're much better off using the Be add-on instead of DOSfs.

To use the Be-provided add-on, just remove DOSfs (or whatever add-on you're uninstalling) from its place in the /home/config/add-ons/ directory.