分号在 bash 命令中运行时有什么作用? [英] What does the semicolon do when it is run in a bash command?

问题描述

例如运行时

echo a; echo b

在终端中，它的输出是:

in the terminal, its output is:

a
b

在我看来，分号等待第一个命令 (echo a) 完成，然后启动第二个命令 (echo b).

It seems to me that the semicolon waits for the first command (echo a) to finish, then it starts the second command (echo b).

问:分号是否只是用于在 bash 中迭代命令?

Q: Is the semicolon just used for iterating over commands in bash?

问:分号在 bash 命令中运行时的作用是什么?

Q: What does the semicolon do when it is run in a bash command?

推荐答案

; 将两个命令分开.

echo a; echo b

它让 bash 知道 echo a 和 echo b 是两个独立的命令，需要一个接一个地单独运行

It lets the bash know that echo a and echo b are two separate commands and need to be run separately one after the other

尝试不使用分号

$ echo a echo b
a echo b

这里的语句被当作单个命令 echo 并且 a echo b 作为参数传递给 echo

Here the statement is taken as a single command echo and a echo b is passed as parameter to the echo

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