#Bash 的 cat 命令
cat [OPTION]... [FILE]...
功能
拼接文件内容并打印到标准输出。
类型
可执行文件（/usr/bin/cat），属于 coreutils。
参数
OPTION选项：-A,--show-all- 显示所有特殊符号；同-vET-b,--number-nonblank- 非空行显示行号-e- 行末显示$，其它不可打印字符显示为^或M-前缀形式；同-vE-E,--show-ends- 行末显示$-n,--number- 显示行号-s,--squeeze-blank- 抑制重复的空行-t- 制表符显示为^I，其它不可打印字符显示为^或M-前缀形式；同-vT-T,--show-tabs- 制表符显示为^I-u- 不进行缓冲；已废弃，被忽略-v,--show-nonprinting- 不可打印字符显示为^或M-前缀形式，参考 ASCII 编码表--help- 显示帮助--version- 显示版本
FILE- 要拼接的文件列表，如果没有这个参数或指定为-，则读取标准输入
#示例
查看文件
$ cat file # 查看 file
$ cat file1 file2 # 查看 file1 和 file2
写文件
$ cat > file # 将标准输入写入 file
- 将标准输入覆盖写入
file文件 - 按
Ctrl + D结束
$ cat >> file # 将标准输入写入 file
- 将标准输入追加写入
file文件 - 按
Ctrl + D结束
$ cat src1 src2 > dest # 将 src1 和 src2 拼接，写入 dest
- 拼接
src1和src2，覆盖写入dest
#相关命令
#推荐阅读
#手册
CAT(1) User Commands CAT(1)
NAME
cat - concatenate files and print on the standard output
SYNOPSIS
cat [OPTION]... [FILE]...
DESCRIPTION
Concatenate FILE(s) to standard output.
With no FILE, or when FILE is -, read standard input.
-A, --show-all
equivalent to -vET
-b, --number-nonblank
number nonempty output lines, overrides -n
-e equivalent to -vE
-E, --show-ends
display $ at end of each line
-n, --number
number all output lines
-s, --squeeze-blank
suppress repeated empty output lines
-t equivalent to -vT
-T, --show-tabs
display TAB characters as ^I
-u (ignored)
-v, --show-nonprinting
use ^ and M- notation, except for LFD and TAB
--help display this help and exit
--version
output version information and exit
EXAMPLES
cat f - g
Output f's contents, then standard input, then g's contents.
cat Copy standard input to standard output.
AUTHOR
Written by Torbjorn Granlund and Richard M. Stallman.
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
tac(1)
Full documentation <https://www.gnu.org/software/coreutils/cat>
or available locally via: info '(coreutils) cat invocation'
GNU coreutils 9.4 April 2024 CAT(1)