Shell编程中的变量【转载】

Linux Shell 变量详解

最新推荐文章于 2021-05-13 05:16:43 发布

转载最新推荐文章于 2021-05-13 05:16:43 发布 · 59 阅读

0 ·

CC 4.0 BY-SA版权

原文链接：https://my.oschina.net/pooz/blog/103490

本文详细介绍了 Linux Shell 中变量的使用方法，包括特殊变量如进程ID、退出状态等，以及如何通过命令行参数传递变量，并利用 shift 命令进行参数的左移操作。

为什么80%的码农都做不了架构师？>>>

Linux Variables

When variables are used they are referred to with the $ symbol in front of them. There are several useful variables available in the shell program. Here are a few:

$$ = The PID number of the process executing the shell.
$? = Exit status variable.
$0 = The name of the command you used to call a program.
$1 = The first argument on the command line.
$2 = The second argument on the command line.
$n = The nth argument on the command line.
$* = All the arguments on the command line.
$# The number of command line arguments.

The "shift" command can be used to shift command line arguments to the left, ie $1 becomes the value of $2, $3 shifts into $2, etc. The command, "shift 2" will shift 2 places meaning the new value of $1 will be the old value of $3 and so forth.

转载于:https://my.oschina.net/pooz/blog/103490