Versions

libc {
  GLIBC_2.0 {
    # global variables
    _errno; __environ; _environ;

    # helper functions
    __errno_location; __libc_init_first; __libc_start_main;

    # Exception handling support functions from libgcc
    __register_frame; __register_frame_table; __deregister_frame;
    __register_frame_info; __deregister_frame_info;

    # variables in normal name space
    environ; errno;

    # b*
    brk;

    # s*
    sbrk;
  }
  GLIBC_2.1 {
    # global variables
    __libc_stack_end;

    # New special glibc functions.
    gnu_get_libc_release; gnu_get_libc_version;
  }
}