#Bash 的 printf 命令
printf [OPTION] FORMAT [ARGUMENT]...
功能
格式化并打印数据。
类型
可执行文件（/usr/bin/printf），属于 coreutils。
参数
OPTION选项：--help- 显示帮助--version- 显示版本
FORMAT- 格式字符串ARGUMENT- 参数列表
#格式
参考 C 语言标准库函数 printf。
| 符号 | 说明 |
|---|---|
\" | 双引号 |
\\ | 反斜杠 |
\a | 警告声（BEL） |
\b | 退格 |
\c | 不再产生任何输出 |
\e | Escape 字符 |
\f | 换页符（form feed） |
\n | 换行符 |
\r | 回车符 |
\t | 水平制表符 |
\v | 垂直制表符 |
\NNN | 八进制值为 NNN 的字节（1 到 3 位） |
\xHH | 十六进制值为 HH 的字节（1 到 2 位） |
\uHHHH | Unicode 字符（ISO/IEC 10646），十六进制值 HHHH（4 位） |
\UHHHHHHHH | Unicode 字符，十六进制值 HHHHHHHH（8 位） |
%% | 百分号（%）本身 |
%b | 将参数作为带有反斜杠转义的字符串输出；八进制转义格式为 \0 或 \0NNN |
%q | 输出可作为 shell 输入的格式，并使用 POSIX 提议的 $'' 语法对不可打印字符进行转义 |
%c | 单个字符 |
%s | 字符串 |
%d | 有符号十进制整数 |
%i | 有符号十进制整数，同 %d |
%u | 无符号十进制整数 |
%o | 无符号八进制整数 |
%x | 无符号十六进制整数，字母小写 |
%X | 无符号十六进制整数，字母大写 |
%f | 浮点数，字母小写 |
%F | 浮点数，同 %f |
%e | 浮点数，科学计数法，字母小写 |
%E | 浮点数，科学计数法，字母大写 |
%g | 浮点数，省略小数末尾的 0，值较大时使用科学计数法，字母小写 |
%G | 浮点数，省略小数末尾的 0，值较大时使用科学计数法，字母大写 |
#示例
$ printf "Hello World\n"
Hello World
$ printf "Name: %s, Age: %d\n" "Alice" 18
Name: Alice, Age: 18
#推荐阅读
#手册
PRINTF(1) User Commands PRINTF(1)
NAME
printf - format and print data
SYNOPSIS
printf FORMAT [ARGUMENT]...
printf OPTION
DESCRIPTION
Print ARGUMENT(s) according to FORMAT, or execute according to OPTION:
--help display this help and exit
--version
output version information and exit
FORMAT controls the output as in C printf. Interpreted sequences are:
\" double quote
\\ 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
\v vertical tab
\NNN byte with octal value NNN (1 to 3 digits)
\xHH byte with hexadecimal value HH (1 to 2 digits)
\uHHHH Unicode (ISO/IEC 10646) character with hex value HHHH (4 digits)
\UHHHHHHHH
Unicode character with hex value HHHHHHHH (8 digits)
%% a single %
%b ARGUMENT as a string with '\' escapes interpreted, except that
octal escapes are of the form \0 or \0NNN
%q ARGUMENT is printed in a format that can be reused as shell in‐
put, escaping non-printable characters with the proposed POSIX
$'' syntax.
and all C format specifications ending with one of diouxXfeEgGcs, with
ARGUMENTs converted to proper type first. Variable widths are handled.
NOTE: your shell may have its own version of printf, which usually su‐
persedes the version described here. Please refer to your shell's doc‐
umentation for details about the options it supports.
AUTHOR
Written by David MacKenzie.
REPORTING BUGS
GNU coreutils online help: <https://www.gnu.org/software/coreutils/>
Report any translation bugs to <https://translationproject.org/team/>
COPYRIGHT
Copyright © 2023 Free Software Foundation, Inc. License GPLv3+: GNU
GPL version 3 or later <https://gnu.org/licenses/gpl.html>.
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.
SEE ALSO
printf(3)
Full documentation <https://www.gnu.org/software/coreutils/printf>
or available locally via: info '(coreutils) printf invocation'
GNU coreutils 9.4 April 2024 PRINTF(1)