用法
命令 操作符号 文件名
操作符号包括：
>：标准输出的重定向到文件，实际是“>”前省略了数字“1”
2>错误输出用
&>所有输出重定向到文件
可以用来分析文件的输出结果
标准输出
$ df -h >file
(base) pc@pc-System-Product-Name:/project/raw_fq$ cat file1
Filesystem Size Used Avail Use% Mounted on
udev 32G 0 32G 0% /dev
tmpfs 6.3G 2.4M 6.3G 1% /run
/dev/nvme0n1p2 228G 11G 207G 5% /
tmpfs 32G 0 32G 0% /dev/shm
tmpfs 5.0M 4.0K 5.0M 1% /run/lock
tmpfs 32G 0 32G 0% /sys/fs/cgroup
/dev/loop0 13M 13M 0 100% /snap/gnome-characters/139
/dev/loop2 2.3M 2.3M 0 100% /snap/gnome-calculator/260
/dev/loop1 36M 36M 0 100% /snap/gtk-common-themes/1198
/dev/loop4 152M 152M 0 100% /snap/gnome-3-28-1804/36
/dev/loop3 141M 141M 0 100% /snap/gnome-3-26-1604/82
/dev/loop5 141M 141M 0 100% /snap/gnome-3-26-1604/74
/dev/loop6 3.8M 3.8M 0 100% /snap/gnome-system-monitor/57
/dev/loop7 4.2M 4.2M 0 100% /snap/gnome-calculator/406
/dev/loop8 1.0M 1.0M 0 100% /snap/gnome-logs/61
/dev/loop9 90M 90M 0 100% /snap/core/6673
/dev/loop10 15M 15M 0 100% /snap/gnome-logs/45
/dev/nvme0n1p1 511M 6.1M 505M 2% /boot/efi
/dev/loop11 35M 35M 0 100% /snap/gtk-common-themes/818
/dev/loop12 91M 91M 0 100% /snap/core/6350
/dev/loop13 15M 15M 0 100% /snap/gnome-characters/254
/dev/loop14 54M 54M 0 100% /snap/core18/941
/dev/loop15 3.8M 3.8M 0 100% /snap/gnome-system-monitor/77
/dev/sda1 7.3T 5.3T 1.6T 78% /data
/dev/sdb1 7.3T 93M 6.9T 1% /public
/dev/sdd1 7.3T 572M 6.9T 1% /home
/dev/sdc1 7.3T 173G 6.7T 3% /project
tmpfs 6.3G 16K 6.3G 1% /run/user/121
tmpfs 6.3G 36K 6.3G 1% /run/user/1000
/dev/loop16 90M 90M 0 100% /snap/core/6818
/dev/loop17 15M 15M 0 100% /snap/gnome-characters/258
/dev/loop18 3.8M 3.8M 0 100% /snap/gnome-system-monitor/81
/dev/loop19 152M 152M 0 100% /snap/gnome-3-28-1804/40
$ df -h > file1
$ diff file1 file
28c28
< /dev/sdc1 7.3T 173G 6.7T 3% /project
---
> /dev/sdc1 7.3T 163G 6.7T 3% /project
标准输出和错误输出分别放两个文件
$ ls /error test >right_file 2>wrong_file
$ cat right_file
test:
hangshu.tex
result.txt
text.txt
$ cat wrong_file
ls: cannot access '/error': No such file or directory
错误和正确的放一个文件
$ ls /error test >all.log 2>&1
$ cat all.log
ls: cannot access '/error': No such file or directory
test:
hangshu.tex
result.txt
text.txt
或者简单写为
ls /error test &>all2.log
$ cat all2.log
ls: cannot access '/error': No such file or directory
test:
hangshu.tex
result.txt
text.txt
