问题：
 root@czu:~# cd /root/桌面/busybox-1.19.3
root@czu:~/桌面/busybox-1.19.3# make menuconfig
  HOSTCC  scripts/basic/fixdep
  HOSTCC  scripts/basic/split-include
scripts/basic/split-include.c: 在函数‘main’中:
scripts/basic/split-include.c:134:11: 警告： 忽略声明有 warn_unused_result 属性的‘fgets’的返回值 [-Wunused-result]
  HOSTCC  scripts/basic/docproc
  GEN     include/applets.h
  GEN     include/usage.h
  GEN     applets/Kbuild
  GEN     coreutils/Kbuild
  GEN     coreutils/Config.in
  GEN     coreutils/libcoreutils/Kbuild
  GEN     procps/Kbuild
  GEN     procps/Config.in
  GEN     mailutils/Kbuild
  GEN     mailutils/Config.in
  GEN     e2fsprogs/Kbuild
  GEN     e2fsprogs/Config.in
  GEN     e2fsprogs/old_e2fsprogs/Kbuild
  GEN     e2fsprogs/old_e2fsprogs/Config.in
  GEN     e2fsprogs/old_e2fsprogs/uuid/Kbuild
  GEN     e2fsprogs/old_e2fsprogs/blkid/Kbuild
  GEN     e2fsprogs/old_e2fsprogs/e2p/Kbuild
  GEN     e2fsprogs/old_e2fsprogs/ext2fs/Kbuild
  GEN     libbb/Kbuild
  GEN     libbb/Config.in
  GEN     printutils/Kbuild
  GEN     printutils/Config.in
  GEN     libpwdgrp/Kbuild
  GEN     debianutils/Kbuild
  GEN     debianutils/Config.in
  GEN     shell/Kbuild
  GEN     shell/Config.in
  GEN     loginutils/Kbuild
  GEN     loginutils/Config.in
  GEN     sysklogd/Kbuild
  GEN     sysklogd/Config.in
  GEN     console-tools/Kbuild
  GEN     console-tools/Config.in
  GEN     init/Kbuild
  GEN     init/Config.in
  GEN     scripts/Kbuild
  GEN     runit/Kbuild
  GEN     runit/Config.in
  GEN     miscutils/Kbuild
  GEN     miscutils/Config.in
  GEN     archival/Kbuild
  GEN     archival/Config.in
  GEN     archival/libarchive/Kbuild
  GEN     modutils/Kbuild
  GEN     modutils/Config.in
  GEN     selinux/Kbuild
  GEN     selinux/Config.in
  GEN     util-linux/Kbuild
  GEN     util-linux/Config.in
  GEN     util-linux/volume_id/Kbuild
  GEN     editors/Kbuild
  GEN     editors/Config.in
  GEN     findutils/Kbuild
  GEN     findutils/Config.in
  GEN     networking/Kbuild
  GEN     networking/Config.in
  GEN     networking/libiproute/Kbuild
  GEN     networking/udhcp/Kbuild
  GEN     networking/udhcp/Config.in
  HOSTCC  scripts/kconfig/conf.o
scripts/kconfig/conf.c: 在函数‘conf_choice’中:
scripts/kconfig/conf.c:354:9: 警告： 忽略声明有 warn_unused_result 属性的‘fgets’的返回值 [-Wunused-result]
scripts/kconfig/conf.c: 在函数‘conf_askvalue’中:
scripts/kconfig/conf.c:106:8: 警告： 忽略声明有 warn_unused_result 属性的‘fgets’的返回值 [-Wunused-result]
  HOSTCC  scripts/kconfig/kxgettext.o
  HOSTCC  scripts/kconfig/mconf.o
scripts/kconfig/mconf.c: 在函数‘show_textbox’中:
scripts/kconfig/mconf.c:839:7: 警告： 忽略声明有 warn_unused_result 属性的‘write’的返回值 [-Wunused-result]
scripts/kconfig/mconf.c: 在函数‘exec_conf’中:
scripts/kconfig/mconf.c:473:6: 警告： 忽略声明有 warn_unused_result 属性的‘pipe’的返回值 [-Wunused-result]
  SHIPPED scripts/kconfig/zconf.tab.c
  SHIPPED scripts/kconfig/lex.zconf.c
  SHIPPED scripts/kconfig/zconf.hash.c
  HOSTCC  scripts/kconfig/zconf.tab.o
  HOSTLD  scripts/kconfig/mconf
  HOSTCC  scripts/kconfig/lxdialog/checklist.o
In file included from scripts/kconfig/lxdialog/checklist.c:24:0:
scripts/kconfig/lxdialog/dialog.h:31:20: 致命错误： curses.h：没有那个文件或目录
编译中断。
make[2]: *** [scripts/kconfig/lxdialog/checklist.o] 错误 1
make[1]: *** [menuconfig] 错误 2
make: *** [menuconfig] 错误 2
root@czu:~/桌面/busybox-1.19.3#
解决办法：
root@czu:~/桌面/busybox-1.19.3# apt-get install libncurses5-dev
原因：
Ubuntu系统中缺少一个套件 ncurses devel ，把此套件安装下即可。

先设定一个root的密码，sudo passwd root
1、先设定一个root的密码，sudo passwd root
2、root 登陆，su root
3、备份一下lightgdm，有备无患。
cp -p /etc/lightdm/lightdm.conf /etc/lightdm/lightdm.conf.bak
4、编辑lightdm.conf
sudo gedit /etc/lightdm/lightdm.conf
5、添加一行：
greeter-show-manual-login=true
修改后为：
[SeatDefaults]
greeter-session=unity-greeter
user-session=ubuntu
greeter-show-manual-login=true
重启登陆即可。已经可以输入root了。