def __distro(self):
        """Based on the Linux distribution, set values accordingly.  A user
        specified value overrides any defaults."""

        if hpccm.config.g_linux_distro == linux_distro.UBUNTU:
            if not self.__ospackages:
                self.__ospackages = ['cpio', 'libnuma1', 'libpciaccess0',
                                     'openssh-client', 'rpm2cpio', 'wget']
                if self.__gnu:
                    self.__ospackages.append('libgfortran3')
            self.__runtime_ospackages = ['libnuma1', 'libpciaccess0',
                                         'openssh-client']
            if self.__gnu:
                self.__runtime_ospackages.append('libgfortran3')

            self.__installer_template = 'cd / && rpm2cpio {} | cpio -id'
        elif hpccm.config.g_linux_distro == linux_distro.CENTOS:
            if not self.__ospackages:
                self.__ospackages = ['libpciaccess', 'numactl-libs',
                                     'openssh-clients', 'wget']
                if self.__gnu:
                    self.__ospackages.append('libgfortran')
            self.__runtime_ospackages = ['libpciaccess', 'numactl-libs',
                                         'openssh-clients']
            if self.__gnu:
                self.__runtime_ospackages.append('libgfortran')

            # The RPM has dependencies on some CUDA libraries that are
            # present, but not in the RPM database.  Use --nodeps as a
            # workaround.
            self.__installer_template = 'rpm --install --nodeps {}'

        else: # pragma: no cover
            raise RuntimeError('Unknown Linux distribution')
Based on the Linux distribution, set values accordingly.  A user
        specified value overrides any defaults.
hpccm/building_blocks/mvapich2_gdr.py