lpi linux essentials

1. What is a shell?The shell is the interface between the user and the Linux operating system.There are multiple shells in Linux, with bash being used by default.Classification of 2.shell(1) BashThe bash Shell is a free version of the Bourne shell, which is the oldest Unix shell, including many additional features. Bash has an editable command line that can be checked back to the history command, enabling t

])-f:forceChapter Two: Creation of file systems (virtual file system for Linux)Learn about the relationships between file systems and Linux virtual file systems wear pieces650) this.width=650; "src=" http://s3.51cto.com/wyfs02/M02/72/89/wKiom1Xlp2zxpzbiAAD6w0OmNCA880.jpg "style=" float: none; "title=" 20150819_6bf934e568ec295e9c2etzmx2ldv0hlf.jpg "alt=" Wkiom1xlp2zxpzbiaad6w0omnca880.jpg "/>Commands you nee

, waste space, but the destruction of two times there is a problem. Because the same object is manipulated at the time of the destruction. So assuming that the object has allocated memory internally, it will cause double free for this memory because the pointer is the same. To open DF the macro experiment:$./tests addr 0x20de010ctor 0x6012b8s addr 0x20de040ctor 0x6012b8...dtor 0x6012b8s addr 0x20de040dtor 0x6012b8s addr 0x20 de040Since both of the destructors are the same object, the memory that

of two files (leaving only files that exist in two files)Comm-1 file1 file2 Compare the contents of two files delete only what ' file1 ' containsComm-2 file1 file2 Compare the contents of two files delete only what ' file2 ' containscomm-3 file1 file2 Compare the contents of two files delete only two files that are common to each othercharacter settings and file format conversionsDos2unix filedos.txt fileunix.txt Convert the format of a text file from Msdos to UnixUnix2dos fileunix.txt filedos.

partitions# swapon-s # View all swap partitions# hdparm-i/dev/hda # View disk parameters (for IDE devices only)# DMESG | grep IDE # VIEW IDE device detection network at startup# ifconfig # View the properties of all network interfaces# iptables-l # view firewall settings# route-n # View the routing table# netstat-lntp # View all listening ports# NETSTAT-ANTP # View all established connections# netstat-s # View the network statistics process# ps-ef # View All Processes# top # Real-time display o

lookup>find/‐name"app*"//Fuzzy Lookup name is the app start file need double >find/‐maxdepth 4‐mindepth 3‐name passwd/3 to 4 Search for a file named passwd between levelsOptions:‐name//Search by file name word for the condition‐maxdepth//Limit the deepest level of lookups‐mindepth//Limit search to the lightest level‐size//Find default units by file size: Five bytes byte units: number C> Find/‐size 50c//Find a file size of 50 bytes in the current folder kilobytes unit: Number KScope of limitatio

Is definitely a boutique, strongly not exclusive, Vi/vim keyboard map. VI is first used in Unix system, it is a text editor, almost all Unix-like machines are provided, learning Linux will need to learn vi/vim, familiar with this keyboard diagram, can help you learn vi/vim. If you want to learn Vi/vim suggest looking for this information, forum should be a lot of.650) this.width=650; "src=" Http://linux.chinaitlab.com/UploadFiles_7565/200811/200811060

CentOS 7.4 Build LnmpLatest versions lnmp:linux7.4, ngnix1.13.9, mysql5.7.20, php7.1.10Directory:The first part of the preparatory workThe second part installs the Nginx serviceThe third part installs the MySQL databasePart IV builds PHP operating environmentPart V LNMP Architecture application (build Discuz forum)The first part of the preparatory workOne: server: Linux system-centos 7.4;IP Address: 192.168.80.10Client: Take WIN7 as an example, test t

view the path to the command Whereis,locate,find1 [[email protected]/]# which CP2 alias cp='cp-i' C18>3 /BIN/CPSomething else besides the command.CpIf you do not want to prompt for confirmation protection under commands such as copy move delete, you need to add "\" to the command before1 [[email protected]/]# cp/tmp/test.txt/mnt/2# #会提示 3 [[email protected]/]# \CP/TM p/test.txt/mnt/4 # #不会提示5 [[email protected]/]#/bin/cp/tmp/test.txt/mnt6 # #另一种方法, the exact location of the command see

Tags: sha wildcard character cat nbsp path usermod list Basic Create a folderBasic command:Create/Modify/delete user Useradd/usermod/userdelCreate/Modify/delete user groups Groupadd/groupmod/groupdelModify the owning user/owning user group Chown/chgrpModify Permissions chmodCreate a folder mkdirCreate a file TouchSwitch Directory CDDelete files/directories RMDisplay list Ls/llEdit Vim/geditOpen File More/less/cat/tailView Help ManShow current working directory PWDMoving MVCopy CP/SCPPermissions:

.jpg "alt=" Wkiol1j6h5oi0xfnaaaxvdmkpyy640.jpg-wh_50 "/>Virsh shutdown Vmname # #正常关闭指定vm650) this.width=650; "Src=" https://s3.51cto.com/wyfs02/M02/92/03/wKiom1j6H6XQ_bwZAAATvUwbWWg865.jpg-wh_500x0-wm_ 3-wmp_4-s_1701111945.jpg "title=" 36020170421225638465.jpg "alt=" Wkiom1j6h6xq_bwzaaatvuwbwwg865.jpg-wh_50 "/>Virsh Destroy Vmname # #强行结束指定vmVirsh Create Vmname.xml # #临时恢复指定vm, Vmname represents the front-end management fileVirsh define Vmname.xml # #永久恢复vmVirsh undefine vmname # #删除vm的前端管理, st

forms:Format 1:For (variable in array)StatementExample:[Email protected] nginx]# awk ' begin{For (k in ENVIRON){Print k "=" environ[k];}}‘awkpath=.:/ Usr/share/awkOldpwd=/home/web97Ssh_askpass=/usr/libexec/openssh/gnome-ssh-askpassSelinux_level_requested=Selinux_role_requested=Lang=zh_cn. GB2312。。。。。。Description: ENVIRON is an awk constant, a sub-typical array.Format 2:for (a variable; a condition; an expression)StatementExample:[Email protected] nginx]# awk ' begin{total=0;for (i=0;i{Total+=i;

delimiter $NF the last field in a row[Email protected] program_test]# awk-f: ' {print $ \ t ' $NF} '/etc/passwdRoot/bin/bashBin/sbin/nologinDaemon/sbin/nologin4), print each letter in the file[email protected] program_test]# cat read_each_word.shCat hello.c | \(While read line;Do#echo $line;for word in $line;Do#echo $word;For ((i=0;iDoEcho ${word:i:1};DoneDoneDone)5), Print 4–6 line content[[email protected] program_test]# SEQ 100 | awk ' nr==4, nr==6 '4566), awk to implement the function simil

root root 7 Jan 2 00:24 100_symbol.txt-100.txt-rw-r--r--. 1 root root 2 00:22 100.txt Find symbolic Link file method one: [[email protected] touch_more]# Ls-al | grep ' ^l ' | awk ' {print $9} '//feature tag, starting with L.100_symbol.txt method Two: [[email protected] touch_more]# find./-type L./100_symbol.txt print Symbolic link to file name: [[email protected] touch_more]# Ls-al 100_symbol.txt |awk ' {print $11} '100.txt6, Traversal files, classification type statistics file[email protected

file-#:1-9 specifies that the compression ratio is 6 by default;UNXZ DecompressionUnxz/path/to/somefile.xzXzdec DecompressionXzcat/path/to/somefile.xz Zip: Compressible directory, compression by default does not delete the original file (both archived and compressed)Zip filename.zip FILE1 FILE2 ...Zip Test.zip test/*Uzip: Unzip Tar: Archive tool (archive not compressed)-C: Create an archive file-F: Specify the Archive file name-X: Expand Archive file--xattrs: Preserve extended properties of

Linux Essentials (keep up with the new ...)Common commands:Linux Shell EnvironmentBash shortcuts that let you boost command-line efficiency [FULL VERSION]Set your own Liux aliasFind use for LinuxLinux command Find real > exampleLinux command Xargs+cutgrep tipsSwitching between a Linux task and a front deskHow Linux run

directory of root super UserLib 32-bit library fileLIB64 64-bit library fileOpt third-party software installation addressUser Software Installation Addressvar frequently transformed data holds address log storage addressThe mount point of the MNT deviceLost+found didn't have time to save the file, the last strawIv. Catalogue of Proc Proc/cpuinfo CPU InformationCat/proc/cpuinfoLscpu Proc/meminof Memory InformationCat/proc/meminofFree-h: Human Readable language Proc/mounts Mounti

;B.Uniq * * You can use this command to delete duplicate rows after sorting is complete (only once)-I: Ignore case differences-C: Counting650) this.width=650; "src=" Http://s5.51cto.com/wyfs02/M00/7F/F9/wKioL1czNgqw77KUAAE-5AkvBZ8638.png "style=" float: none; "Title=" Linux base 44. PNG "alt=" Wkiol1czngqw77kuaae-5akvbz8638.png "/>c.WC * * overall data for calculating the output information -L: List only travel-W: Only How many words (English word)-M:

1.1 Garbled Reason:? The character set of Linux differs from the character set of a remote connection1.2 Troubleshooting?1.3 How to fix (how to modify the Linux character set)? View the garbled structure map URL; https://www.processon.com/view/link/59e978b0e4b0c86d400de71c2nd Chapter Linux Directory Structure-Features2.1 Directory structure features? Upside down

be consistent with the set of character sets at Oracle installation, such as: ZHS16GBK, otherwise the data import export Chinese garbled problem: Wq ! #保存退出 source. bash_profile #使设置立刻生效 3. Oracle Installation Direct installation, the middle will have the process of checking the package, if a package is missing, if there is no network, you need to configure the local image in Yum as a local source, as follows Mount the ISO or DVD first Mount –o loop–t iso9660 centos-6.0-i386-bin-dvd.iso Moun