Shulou(Shulou.com)06/01 Report--

Editor to share with you what are the Shell commands in Linux, I believe most people do not know much about it, so share this article for your reference, I hope you can learn a lot after reading this article, let's go to know it!

(1) the normal operation we need is

$ps | grep xxx $kill-9 xx

(2) the kill command is commonly used, but using the killall command is faster.

$killall-9 xxx

(3) what bothers me is that the one I use doesn't have killall, and then I do the following

$adb shell ps | grep speech | awk'{print $2}'> 1.txt $cat 1.txt | xargs-N1 adb shell kill-9

The reason I use this is that redirection with one instruction is always a problem, and normally this one is fine.

$adb shell ps | grep speech | awk'{print $2}'| xargs-N1 kill-9

1. Shutdown / restart

Shutdown (must use root user) shutdown-h now # # shut down immediately shutdown-h + 10 # # 10 minutes later shutdown shutdown-h 12:00:00 # # shutdown halt # equals immediate shutdown and restart shutdown-r now

2. Echo

Root@ubuntu:~# a = "hello,world" root@ubuntu:~# echo an a root@ubuntu:~# echo & a [1] 3091 a: command not found [1] + Done echo root@ubuntu:~# echo $a hello,world root@ubuntu:~#

3. Vim text editor

The most basic usage vi somefile.4 1 will first enter the "general mode", which only accepts all kinds of shortcut keys, but cannot edit the contents of the file. 2 press the I key, and you will enter the editing mode from the general mode. In this mode, what is typed in is the file content 3. After editing, press the ESC key to exit the editing mode and return to the general mode. 4 press: again, enter the "bottom line command mode" and enter the wq command Enter you can enter some useful shortcuts (used in general mode): an insert An at the end of the cursor insert An at the end of the line I insert gg at the front of the line jump directly to the first line of the file G jump directly to the last line of the file dd delete line 3dd delete 3 lines yy copy 3 lines 3yy copy 3 lines p paste u Undo v enters character selection mode After selection, press y to copy, press p to paste ctrl+v to enter block selection mode, press y to copy, press p to paste shift+v to enter row selection mode, press y to copy, press p to paste to find and replace 1 display line number: set nu 2 hide line number: set nonu 3 find keywords: / you # # effect: find the you that appears in the file, and navigate to the first place to find it. Press n to navigate to the next matching location (press N to navigate to the previous one) 4 replace operation: s/sad/bbb finds the first sad on the line of the cursor, replace with bbb:% s/sad/bbb find all sad in the file, replace with bbb

4. Copy / delete / move / change file name

Cp somefile.1 / home/hadoop/ rm / home/hadoop/somefile.1 rm-f / home/hadoop/somefile.1 mv / home/hadoop/somefile.1.. / mv a.txt b.txt / / rename a.txt to b.txt

5. Packing and compressing

1. Gzip compress gzip a.txt 2, extract gunzip a.txt.gz gzip-d a.txt.gz 3, bzip2 compress bzip2 a 4, extract bunzip2 a.bz2 bzip2-d a.bz2 5, package: tar-cvf bak.tar. / aaa append / etc/password files to bak.tar tar-rvf bak.tar / etc/password 6, extract tar-xvf bak.tar 7, package and compress tar-zcvf a.tar.gz aaa/ 8, Unpack and decompress (say important things three times!) Tar-zxvf a.tar.gz extract to / usr/ tar-zxvf a.tar.gz-C / usr 9, view the contents of the package tar-ztvf a.tar.gz zip/unzip 10, package and compress into bz2 tar-jcvf a.tar.bz2 11, extract bz2 tar-jxvf a.tar.bz2

6. The use of common lookup commands

1. Find the path where the executable command is located: which ls 2, the location of the executable command and help: whereis ls 3, start with a folder to find the file find /-name "hadooop*" find /-name "hadooop*"-ls 4, find and delete find /-name "hadooop*"-ok rm {}\; find /-name "hadooop*"-exec rm {}\ 5. Find the file find / usr-user hadoop-ls 6 with user hadoop, the folder find / home-user hadoop-type d-ls 7 with user hadoop, find /-perm-777-type d-ls 8 with permission 777, look for a file find. / sound/-iname ft56Q.c 9 in the specified directory regardless of case, and display the command history history.

7. Grep command

The most commonly used-full-word matching grep-wrn weiqifa. / sound/ looks for a string but does not look for grep-E "http" in the specified folder. /-R-- exclude-dir=./sound/ grep-E "http". -R-- exclude-dir= {.git, res,bin} excludes files with java and js extensions grep-E "http". -R-- exclude=*. {java,js} 1 basically query the line containing hadoop grep hadoop / etc/password grep aaa. / * .txt 2 cut intercept to: split and retain the seventh segment root@ubuntu:~/kernel_rk3399_yan4_dev/kernel# grep dsl / etc/passwd | cut-d:-f7 / bin/bash root@ubuntu:~/kernel_rk3399_yan4_dev/kernel# grep dsl / etc/passwd dsl:x:1000:1000:dsl / home/dsl:/bin/bash root@ubuntu:~/kernel_rk3399_yan4_dev/kernel# 3 query lines that do not contain hadoop grep-v hadoop / etc/passwd 4 regular expression contains hadoop grep 'hadoop' / etc/passwd 5 regular expression (dot represents any character) grep 'h.etc/passwd 6 regular expression begins with hadoop grep' ^ hadoop' / etc/passwd 7 regular expression ends with hadoop grep 'hadoop$' / etc/passwd rule:. Any character a *: any number of a (zero or more a) a?: zero or one an a +: one or more a. *: any number of arbitrary characters\. Escape. O\ {2\}: O repeat looking for lines that do not begin with # grep-v'^ # 'a.txt | grep-v' ^ $'grep' ^ [hr]'/ etc/passwd that begins with h or r is not grep'^ [^ hr]'/ etc/passwd that begins with h and r is not grep'^ [^ hr]'/ etc/passwd beginning with h to r

8. Interpretation of the description format of linux file permissions

Drwxr-xr-x (you can also denote 111101-> 755 in binary) d: identify the node type (d: folder -: file l: link) r: readable w: writable x: executable the first set of rwx: # # indicates the permissions of the owner of this file: readable, writable, executable, the second set of rmurx: # # indicates this Permissions of the group to which the file belongs to it: readable Unwritable, executable the third group rmurx: # # indicates the permissions of other users of this file (as opposed to the above two types of users) to it: readable, unwritable, executable

9. Modify file permissions

Chmod g-rw .dat # # means to revoke the rw permission of .dat to the group to which it belongs. Chmod o-rw .dat # # means to revoke the rw permission of .dat to other people. Chmod ubix .dat # # means to increase the permission of .dat to its user x chmod a mae x .dat # # means to revoke the x right of .dat to its user. The limit can also be modified digitally. Chmod 664 .dat will be changed to rw-rw-r-- if you want to modify all the content permissions of a folder. The-R parameter chmod-R 770 aaa/ can be used.

10. Modify file ownership

Chown angela aaa # # change user chown: angela aaa # # change group chown angela:angela aaa/ # # modify user and group at the same time

11. Count the size of files or folders

Root@ubuntu:~/kernel_rk3399_yan4_dev/kernel# du-sh sound/ 33m sound/ root@ubuntu:~/kernel_rk3399_yan4_dev/kernel# df-h View disk space root@ubuntu:~/kernel_rk3399_yan4_dev/kernel# df-h Filesystem Size Used Avail Use% Mounted on udev 1.9G 0 1.9G 0% / dev tmpfs 394M 6.4m 388m 2% / Run/ dev/sda1 294G 93G 186G 34% / tmpfs 2.0G 204K 2.0G 1% / dev/shm tmpfs 5.0M 4.0K 5.0M 1% / run/lock tmpfs 2.0G 02.0G 0% / sys/fs/cgroup tmpfs 394M 80K 394m 1% / run/user/1000 root@ubuntu:~/kernel_rk3399_yan4_dev/kernel # these are all the contents of the article "what are the Shell commands in Linux?" Thank you for reading! I believe we all have a certain understanding, hope to share the content to help you, if you want to learn more knowledge, welcome to follow the industry information channel!

Welcome to subscribe "Shulou Technology Information " to get latest news, interesting things and hot topics in the IT industry, and controls the hottest and latest Internet news, technology news and IT industry trends.