libc {

  GLIBC_2.0 {

    # helper functions

    __libc_init_first; __libc_start_main;

  }

  GLIBC_2.1 {

    # New special glibc functions.

    gnu_get_libc_release; gnu_get_libc_version;

  }

  GLIBC_PRIVATE {

    errno;

  }

}