Use the --conflicts option to check what conflicts with a given package. The basic syntax is:

rpm –q query_options --conflicts packages

For example:

# rpm -q --conflicts httpd

thttpd

This command tells you that the httpd package (the Apache Web server) conflicts with the thttpd package. Both packages provide a similar capability. By marking the conflict, the httpd package tells you that you cannot normally install both the httpd and thttpd packages on a system. This information comes from the httpd package, which has an entry in the package that indicates the conflict. The conflict is not guaranteed. These packages may work together, but the creator of the httpd package felt that httpd would not work with the thttpd package and helpfully let us all know.

The RPM system will report on the conflicts and indicate an error if you try to install conflicting packages. The idea of conflicts really gives package creators a way to alert users to potential problems and to tell us that one package likely won’t work with another.

The force options discussed in Chapter 3, Using RPM allow you to override conflicts, if absolutely necessary. In most cases, though, a conflict presents you with the choice to install one or the other of the packages, but not both.