to erase packages, it became common for people to joyfully erase packages until something broke.
Usually this only bit people once, but even once was too much of a hassle if it could be prevented. With this in mind, the RPM developers gave RPM the ability to:
Build packages that contain information on the capabilities they require.
Build packages that contain information on the capabilities they provide.
Store this "provides" and "requires" information in the RPM database.
requirements.
With these features in place, it became more difficult for someone to unknowingly erase a package and wreak havoc on their system.
We've already alluded to the underlying concept for RPM's dependency processing. It is based on two key factors:
Packages advertise what capabilities they provide.
Packages advertise what capabilities they require.
package, that package cannot be installed and expected to work properly.
On the other hand, if a package is to be erased, but its capabilities are required by other installed packages, then it cannot be erased without causing other packages to fail.
As you might imagine, it's not quite that simple. But adding dependency information can be easy. In fact, in most cases, it's automatic!
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