Translations:Binary package guide/56/en
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Next to these, Portage can check if the binary package is built using the same USE flags as expected on the client. Unless using --usepkgonly (-K) or --getbinpkgonly (-G), if a package is built with a different USE flag combination, Portage will either ignore the binary package (and use source-based build) or fail, depending on the options passed to the emerge command upon invocation (see Installing binary packages).