14、Linux-Shell03：echo、printf和test命令

目录

一、echo

二、printf

三、test

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一、echo

echo用于输出字符串

值得关注的地方

1、转义字符\。例如，echo "\"Hello,World\" is a classic sentence for programmer"。

2、read命令用于读取一行的输入，echo可以对输入进行输出

3、\n换行，\c不换行。需要在前面加上-e才会生效。

[root@VirTrxcx test]# cat var.sh 
#! /bin/bash
echo This is a simple test.
echo Now please input a number you are thinking now:
read number
echo -e "Now,I know \c"
echo -e "you are thinking ${number}, right?\n"
echo This is another.

[root@VirTrxcx test]# ./var.sh 
This is a simple test.
Now please input a number you are thinking now:
20
Now,I know you are thinking 20, right?

This is another.

4、echo message > file

输出内容到文件，文件不存在会创建并写入，文件已存在则会覆盖内容。