NAME
echo - display a line of text
名称：echo 显示一行文本
SYNOPSIS
echo [SHORT-OPTION]... [STRING]...
echo LONG-OPTION
简介：echo [参数]... [字符串]...
DESCRIPTION
Echo the STRING(s) to standard output.
描述：输出字符串用标准模式
1 参数 -n 不输出结尾的换行符,即不换行输出
-n do not output the trailing newline
[root@DB104 tmp]# echo -n "My home dir is:$HOME my current dir is:`pwd`"
2 参数-e启用反斜杠符的解释-e enable interpretation of backslash escapes
3 参数-E禁用反斜杠符的解释
-E disable interpretation of backslash escapes (default)
4 参数--help 禁用这个帮助并退出
--help display this help and exit
5 参数--version 输出版本信息并退出
--version output version information and exit
If -e is in effect, the following sequences are recognized:
如果-e起作用，下面的参数是被承认的
\\ backslash
\a alert (BEL)
\b backspace
\c produce no further output
\e escape
\f form feed
\n new line
\r carriage return
\t horizontal tab
\0NNN byte with octal value NNN (1 to 3 digits)
\xHH byte with hexadecimal value HH (1 to 2 digits)
NOTE: your shell may have its own version of echo, which usually super-
sedes the version described here. Please refer to your shell?. documenta-
tion for details about the options it supports.