Returns whether the url of mimetype is executable. To be executable the file must pass the following rules: -# Must reside on the local filesystem. -# Must be marked as executable for the user by the filesystem. -# The mime type must inherit application/x-executable or application/x-executable-script. To allow a script to run when the above rules are satisfied add the entry @code X-KDE-IsAlso=application/x-executable-script @endcode to the mimetype's desktop file.