Linux Shell Notes

Cat  /etc/passwd   All system user accounts list and basic information for each user cat/etc/meminfo the current state of the virtual memory ipcs-m   View the Shared memory page on the current system  [[email  protected]~] #当前shell的用户名, current Virtual Console number, current directory  ls-f differentiate files and directories ls-a hidden files and directories are listed ls-f-r ls-l long tabular format output file type & nbsp; directory d file-character file C block file Bls-sail  -S list file block size  -a list all files   -i lists each file's index node-L produces a long list ls-l test*   Fuzzy query  touch test1 Create an empty file  CP test1 test2  test2 Create a standalone file for a new or existing file   hard link It contains the information and location of the source file. Referencing a hard-link file is equivalent to referencing a source file to create a hard link between files on the same storage medium, and you cannot create a hard link between files under different mount points. However, you can create a soft link under a different mount point. ln-s test1 test2  - s add a parameter to create a soft link, without adding a hard link.  mv test1 test2 Rename file  rm-rf test1 Delete folder-R recursively delete all files under Test1  -f no longer confirm whether to delete  mkdir D IR1 Create a directory  stat test1 provide all the status information for a file on the file system   file test1 view file type  cat test1 view file contents-N All rows plus line number-B only adds a line with text content Line number  more Test1 viewing the contents of a file can be manipulated in the background less test1 view the contents of the file more advanced More tail-f test1  -f allows you to view the contents of a file while other processes are using the file remain active   Real-time Monitoring system log!!! Head Test1 View the contents of the file  ps-ef  -e specifies that all processes running on the system-F extend the output   tOP Real-time monitoring process  kill-9 Java kill Java process   signal     name     Description 1        hup     Hang 2        int     Interrupt 3        quit   End Process 9       &NB Sp KILL     Unconditionally terminate  mount output current system mounted device list mount-t type device dir             type parameter Specifies the file system type for which the disk is formatted MOUNT-T vfat  /dev/sdb1    /media/disk     Manual USB drive/DEV/SDB1 mount to/media/disk  umount uninstalling the device  DF viewing the usage of all mounted disks df-h        -H human-readable form  du is a quick way to determine if there is a large file on a directory on the system and Nbsp;sort test1 sort sort-n test1-n Sort by number rather than by character  grep Hadoop search data   View global variables PRINTENV system environment variables are all capitalized, While the user-defined environment variable is in lowercase echo $JAVA _home View a single environment variable   view local environment variable set setting environment variable  test=testingecho $testtesting setting environment variables with spaces test= Testing a long Stringecho $testtesting a long string  delete an environment variable unset  view an existing alias list alias-p   create your own alias command alias Li= ' Ls-il '

Linux Shell notes