# 第三部分 shell进阶

## 目录

* [9. 换个角度看变量](/shell/part3/09_another_look_at_variables.md)
  * [9.1 内部变量](/shell/part3/09_another_look_at_variables/09_1_internal_variables.md)
  * [9.2 变量类型标注：`declare` 与 `typeset`](/shell/part3/09_another_look_at_variables/09_2_typing_variables_declare_or_typeset.md)
    * [9.2.1 `declare` 的另类用法](/shell/part3/09_another_look_at_variables/09_2_typing_variables_declare_or_typeset/09_2_1_another_use_for_declare.md)
  * [9.3 `$RANDOM`：生成随机数](/shell/part3/09_another_look_at_variables/09_3_random_generate_random_integer.md)
* [10. 变量处理](/shell/part3/10_manipulating_variables.md)
  * [10.1 字符串处理](/shell/part3/10_manipulating_variables/10_1_manipulating_strings.md)
    * [10.1.1 使用 `awk` 处理字符串](/shell/part3/10_manipulating_variables/10_1_manipulating_strings/10_1_1_manipulating_strings_using_awk.md)
    * [10.1.2 参考资料](/shell/part3/10_manipulating_variables/10_1_manipulating_strings/10_1_2_further_reference.md)
  * [10.2 参数替换](/shell/part3/10_manipulating_variables/10_2_parameter_substitution.md)
* [11. 循环与分支](/shell/part3/11_loops_and_branches.md)
  * [11.1 循环](/shell/part3/11_loops_and_branches/11_1_loops.md)
  * [11.2 嵌套循环](/shell/part3/11_loops_and_branches/11_2_nested_loops.md)
  * [11.3 循环控制](/shell/part3/11_loops_and_branches/11_3_loop_control.md)
  * [11.4 测试与分支](/shell/part3/11_loops_and_branches/11_4_testing_and_branching.md)
* [12. 命令替换](/shell/part3/12_command_substitution.md)
* [13. 算术扩展](/shell/part3/13_arithmetic_expansion.md)
* [14. 休息时间](broken://pages/-M1hSOoLr02rVG-KTAFv)


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