mowatermelon
commented
3 years ago cat 指令学习
基础介绍
$ cat [-benstuv] [file ...]
$ cat xxsplit*>xx.mp4 && ls | grep xx
xx.mp4
xxsplitaaaaa.mp4
xxsplitaaaab.mp4
xxsplitaaaac.mp4
xxsplitaaaad.mp4
xxsplitaaaae.mp4将符合条件的文件进行合并输出
参数说明
参数表格
| 参数名 | 参数值说明 | 中文含义 |
|---|---|---|
| b | Number the non-blank output lines, starting at 1. | 在文件第一列，添加合并内容在原文件中的行索引 |
| e | Display non-printing characters (see the -v option), and display a dollar sign ($') at the end of each line.|添加$`换行符做为换行符 |
|
| n | Number the output lines, starting at 1. | 在文件第一列，添加合并内容在合并文件中的行索引 |
| s | Squeeze multiple adjacent empty lines, causing the output to be single spaced. | 除掉连续的空行，调整为单行空行 |
| t | Display non-printing characters (see the -v option), and display tab characters as ^I'.|显示tab 占位为^I'. |
|
| u | Disable output buffering. | |
| v | Display non-printing characters so they are visible. Control characters print as ^X' for control-X; the delete character (octal 0177) prints as^?'. Non-ASCII characters (with the high bit set) are printed as `M-' (for meta) followed by the character for the low 7 bits. |
显示默认不占位显示的字符 |
添加原文件行索引的效果
28 12
29 9
30 4
31 5
1 1
2 2
3 34
4 4
5 5
6 6
7 7
8 8
9 9
10 0
11 12
12 35
添加
e换行符的效果
1$
2$
34$
4$
5$
6$
7$
8$
9$
0$
12$
35$添加合并文件行索引的效果
32 12
33 9
34 4
35 5
1 1
2 2
3 34
4 4
5 5
6 6
7 7
8 8
9 9
10 0通过 man cat 进入说明，按
q键直接退出
$ man cat
CAT(1) BSD General Commands Manual CAT(1)
NAME
cat -- concatenate and print files
SYNOPSIS
cat [-benstuv] [file ...]
DESCRIPTION
The cat utility reads files sequentially, writing them to the standard output. The file operands are processed in command-line order. If file is a single dash (`-') or absent, cat reads from the standard input. If file is a UNIX domain socket, cat connects to it and then reads it until EOF. This complements the UNIX domain binding capability available in inetd(8).
The options are as follows:
-b Number the non-blank output lines, starting at 1.
-e Display non-printing characters (see the -v option), and display a dollar sign (`$') at the end of each line.
NAME
cat -- concatenate and print files
SYNOPSIS
cat [-benstuv] [file ...]
DESCRIPTION
The cat utility reads files sequentially, writing them to the standard output. The file operands are processed in command-line order. If file is a single dash (`-') or absent, cat reads from the standard input. If file is a UNIX domain socket, cat connects to it and then reads it until EOF. This complements the UNIX domain binding capability available in inetd(8).
The options are as follows:
-b Number the non-blank output lines, starting at 1.
-e Display non-printing characters (see the -v option), and display a dollar sign (`$') at the end of each line.
-n Number the output lines, starting at 1.
-s Squeeze multiple adjacent empty lines, causing the output to be single spaced.
-t Display non-printing characters (see the -v option), and display tab characters as `^I'.
-u Disable output buffering.
-v Display non-printing characters so they are visible. Control characters print as `^X' for control-X; the delete character (octal 0177) prints as `^?'. Non-ASCII characters (with the high bit set) are printed as `M-' (for meta) followed by the character for the low 7 bits.
EXIT STATUS
The cat utility exits 0 on success, and >0 if an error occurs.
EXAMPLES
The command:
cat file1
will print the contents of file1 to the standard output.
The command:
cat file1 file2 > file3
will sequentially print the contents of file1 and file2 to the file file3, truncating file3 if it already exists. See the manual page for your shell (i.e., sh(1)) for more information on redirection.
The command:
cat file1 - file2 - file3
will print the contents of file1, print data it receives from the standard input until it receives an EOF (`^D') character, print the contents of file2, read and output contents of the standard input again, then finally output the contents of file3. Note
that if the standard input referred to a file, the second dash on the command-line would have no effect, since the entire contents of the file would have already been read and printed by cat when it encountered the first `-' operand.
split 指令学习
基础介绍
按照固定行数或者估计大小分割单个文件，分割完成是没有后缀名的
参数说明
-l参数，这个参数不起效果比较可惜的是 Linux 下，还支持
-d让后缀默认按照数字格式进行增长，Mac 上没有