linux 命令 cat 的介绍和使用案例
cat 命令是 Linux 中一个非常基础且实用的命令,主要用于查看和处理文本文件的内容。它的名字来源于“concatenate”,意为连接
命令介绍基本语法bashcat [OPTION] [FILE...]OPTION:可选参数,用于修改 cat 命令的默认行为。FILE:一个或多个要处理的文件名。如果没有指定文件,cat 将从标准输入读取内容。常用选项-n:为所有输出行编号。-b:仅对非空行编号。-s:压缩连续的空白行,只显示一行空白行。-E:在每行的末尾显示 $ 符号。-T:将制表符显示为 ^I。-v:显示不可打印字符。命令功能:
root@meng:~# which cat
/usr/bin/cat
root@meng:~# cat --help
Usage: cat [OPTION]... [FILE]...
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.
GNU coreutils online help: <https://www.gnu.org/software/coreutils/>
Report any translation bugs to <https://translationproject.org/team/>
Full documentation <https://www.gnu.org/software/coreutils/cat>
or available locally via: info '(coreutils) cat invocation'
root@meng:~# cat
命令案例:
root@meng:~# cat
ls
ls
whoami
whoami
this is a cat^[[6~
this is a cat
root@meng:~# cat f1.txt.bz2
BZh91AY&SYʗbǐ !aw$S
6/ root@meng:~#
root@meng:~#
root@meng:~#
root@meng:~# cat rec00001f1.txt
f1
root@meng:~# cat f1.txt.bz2 rec00001f1.txt > meng.txt
root@meng:~# cat meng.txt
BZh91AY&SYʗbǐ !aw$S
6/ f1