Linux Study Notes (sorting records)

Linux Study Notes (sorting records)
1. install 2. laruence's Linux Command Learning (1): displays the language currently supported by the system: echo $ LANG (2): modifies the language to English: LANG = EN_US (3 ): command for displaying date and Time: date + % y-% m-% d (4): Command for displaying calendar: cal 2015 (5): easy to use computer: bc exit command quit 3. command learning in Linux learning, if we want to use linux commands, we need to switch to the administrator user. Below is a simple arrangement of commonly used commands in Linux (1 ): su-if the current user is a common user, enter su-to switch to the administrator user (root). If you want to switch to another user, enter the su-user name, for example, su-hanyinglong (2 ): shutdown-h now shutdown now command (3): shutdown-r now = reboot restart now (4): log out from the current user (if it is a graphical terminal, enter Exit command to exit the current user) (5): Switch the cd directory (for example, cd/indicates to switch to the linux root directory (/indicates the root directory) (6 ): pwd displays the command in which path the user is currently running (if you do not know the current folder in the command line, enter the command pwd) (7): useradd username, add a user (8): passwd user name, change the password for the specified user name (9): userdel user name, delete a user, however, the user's subfolders in the home folder will be retained (10): userdel-r username, delete a user, and delete the subfolders together with the user in the home folder. (11): ls for example: ls/home lists all the files and directories under Home (12): ls-l for example: a long list of files and directories listed by ls-l/home is displayed (13): ls-a For example: ls-a/home lists hidden files and directories (14 ): mkdir For example: mkdir han create directory (15): rmdir For example: rmdir han can only delete empty directories. If there are other files in this directory, the command is invalid (16): touch for example: touch han. java creates an empty file (17): cp such as cp/home/ken. java/set the ken in the home path. copy the java file to cp-r dir1 dir2 in the root directory (-r indicates recursion. copy the files in the folder represented by dir1 to the dir2 path), for example, cp-r/home/ken. java/(replace the ken. copy the java file to the root directory) (18): mv such as mv/home/ken. Java/move the ken. java file in home to the root directory. Mv, for example,/ken. java/Kencery. java. change the java file name to Kencery. java rm such as rm/Kencery. java uses the Kencery in the root directory. java Delete (if the file is a folder, it cannot be deleted ). Rm-rf * ([-r indicates recursion, f indicates force DELETION], delete all contents, including directories and folders) such as rm-rf/home/ken. java (Force Delete the ken under home. java folder ).