linux learning curve

keyboard through a serial line, which is later replaced by a keyboard and a display, so it is now more appropriate to call the terminal.　　A terminal is a type of character device that has many types, usually using a TTY for short-range end devices. 2. Pty (virtual Terminal): But do we need a terminal interaction if we telnet to the host or use xterm remotely?Yes, this is Virtual Terminal pty (Pseudo-tty) 3. PTS/PTMX (PTS/PTMX is used in conjunction to achieve Pty): pts (pseudo-terminal slave) i

Pipe command Symbol |The standard output of the previous command as the standard Input command for the post command a | Command b Input and output redirection650) this.width=650; "src=" Http://s4.51cto.com/wyfs02/M01/8D/60/wKioL1iakBqxOsD1AAB55stGLUg656.png "title=" _ 20170208112623.png "width=" height= "198" border= "0" hspace= "0" vspace= "0" style= "width:500px;height:198px;" alt= " Wkiol1iakbqxosd1aab55stglug656.png "/>650) this.width=650; "src=" Http://s1.51cto.com/wyfs02/M02/8D/63/wKiom1

informationTemp: Temp directory, the system will automatically deleteUSR: Saving general application softwarevar: keep some frequently changing information, such as log, System logBin: The executable file is saved, the binary is the commandBoot: Boot directory, operating system startup load, including version kernel file, Greb boot program ...Dev: Hardware device files, such as hard disk, network card, sound card, terminal, video card, each of which will be abstracted as a fileETC: Most of the

Directory Management:LS, CD, pwd, mkdir, rmdir, treeFile Management:Touch, stat, file, RM, CP, MV, NanoDate Management:Date, clock, Hwclock, CalTo view text:Cat, TAC, more, less, head, tailCat: Connect and display the positive sequence display (dump directly shows all information without a split screen display)-N: Show line numbers-e: Show line breaksTAC: Similar to cat just in reverse displayMORE: The class is on the man display does not support forward flipping (but can be used to turn up a li

)[]: Optional... : multiple times can occur|: Choose one More{}: GroupingMans:Name: command names and features brief descriptionSynopsis: Usage notes, including available optionsDESCRIPTION: A detailed description of the command function, which may include the meaning of each optionOptions: Explaining the meaning of each optionBUGS:EXAMPLES: Using the exampleSee ALSO: Another referenceFlip Screen:Turn back one screen: SPACETurn One screen forward: bTurn back one line: ENTERTurn One line forward:

1. Drwxr-xr-x1th Letter: indicates file typed -------for file directory (directory)- -------represents a binary filel -------means soft link file (link)第2-4 Letter: indicates the owner (user,owner) of this file has permissionsThe R -------represents Read permission , readw -------indicates write permission, Writex -------represents execute permission, Execute第5-7: permissions of the group to which the file belongs (group)The permissions that the user of this file owner has in the same group.The

packages:cp-r/root/iso/packages//var/www/html/centos6.6/Iv. starting the Apache Server serviceViewing httpd Status: Services httpd statusModify the Centos-local.repo configuration file: Baseurl=file:///root/iso change to Http://192.168.146.233/centos6.6/Packages/Shut down firewall: Service iptables stopStart httpd Services: Service httpd startWeb Access httpd startup is normal: http://192.168.146.233/centos6.6/Packages/Switch to Packages directory: cd/var/www/html/centos6.6/packages/#开始制作repoda

the default permissions that correspond to the defaults.[[email protected] ~]# umask-su=rwx,g=rx,o=rx[[email protected] ~]# mkdir/tmp/test[[email protected] ~]# ls-ld/tmp/tes Tdrwxr-xr-x. 2 root root 4096 January 8 00:32/tmp/test[[email protected] ~]#When creating a new file, the default is no execute permission for security purposes. For example, create a new Test1.txt file under the TMP directory with the following default permissions:[Email protected] ~]# touch/tmp/test1.txt[[email protect

7949155da5da74af9b92c172687b290a773df-c7-x86_64- Comps.xml.gza0af68e1057f6b03a36894d3a4f267bbe0590327423d0005d95566fb58cd7a29- Other.xml.gzb686d3a0f337323e656d9387b9a76ce6808b26255fc3a138b1a87d3b1cb95ed5-primary.xml.gzc1561546c684bd06b3a499c2babc35 C761b37b2fc331677eca12f0c769b1bb37-filelists.xml.gzcf0cc856d46b3095106da78256fb28f9d8defea4118d0e75eab07dc53b7d3f0d-other . sqlite.bz2repomd.xmlrepomd.xml.asctrans.tbl[[emailprotected]~] #cp/misc/cd/repodata/ 38b60f66d52704cffb8696750b2b6552438c1ace2

directory and sub-directoryFind.2. Find the file name ending in. txt in the/admin directory Find/admin-iname "*.txt"3. Find files not ending with . txt under /adminFind/admin! -name "*.txt"4. Find all files ending in. txt and . pdf Under the current directory and sub-directory Find. -name "*.txt"-o-name "*.pdf"5. Matching file path or filefind/admin/-path "*user*"6. Matching file paths based on regular expressionsFind. -regex ". *\ (\.txt\|\.pdf\) $"7. Search for all files with a dept

(else)If [conditional judgment]; ThenWhen the conditional judgment is established, the instruction work content can be carried out;ElseWhen the conditional judgment is not established, the instruction work content can be carried out;Fi# Multiple conditional judgments (if ... else) are performed in a number of different situations (if elif ... elif)If [conditional judgment type one]; ThenWhen the conditional judgment is established, the instruction work content can be carried out;elif [condition

variable contentsAlias Settings Alias,unaliasData Flow re-orientation1. Standard input (stdin): code 0, use 2. Standard output (STDOUT): Code 1, using > or >>;3. Standard error Output (STDERR): Code 2, using 2> or 2>>;Save stdout not stderr to separate files.[Email protected] ~]$ find/home-name BASHRC > List_right 2> list_error/dev/null Trash CansWrite Find/home-name. bashrc > List 2>1The basis for the judgment of the Order execution:; , , | |CMD; CMD (continuous instruction release without reg

Tags: Linux ops i Linux learning Linux basic Linux cloud computingSersync uses inotify technology to realize real-time synchronization of water server data, which monitors the change of file system on sersync server,rsync is a widely used local and offsite data Synchronizati

the device model in 2410. URL: Http://blog.chinaunix.net/u1/41638/showart_438078.html (4) luofuchong's blog, who analyzed some Linux subsystems (such as SPI and input) in 2410, is very powerful and worthy of attention. Web: http://www.cnitblog.com/luofuchong/ In this part of learning, we will first study each element of the Linux device model, and finally

line to turn off SELinux and SELinux will open the next time you restart Linux.Method Two:#vi/etc/selinux/configselinux=disabled//change SELinux to Disabled. In addition, enforcing represents execution, and permissive represents freedom.Save restart after #reboot//change.6. Set Putty to login via keyOpen Putty.exe Click on your saved session, then click on the right side of the "Load", on the left, click on the "SSH" front of the + and then select "Auth", see the right "Private key file for aut

the syntax in the following format:Traceroute website(9) NetstatThe netstat command is used to display network-related information , where the path is/bin/netstat, with the syntax in the following format:netstat [options]where the-t option represents the TCP protocol, the-U option represents the UDP protocol,-L for listening,-R for routing, and-n for displaying the IP address and port number .such as: view the local listening port-----netstat-tlunView all network connections on this computer---

default value by executing the umask command again, and the new permission will overwrite the old.Cannot have execute permissions based on security considerationsSet limit file default Permissions command format:umask [OPTION] [ARGS]OPTION:-S output a permission mask in symbolic form[Email protected] lab]# umask-sU=rwx,g=rx,o=rxDefault root masking code: 0022Default masking code for normal users: 0002Normal file initialization permissions are: 666The directory file initialization permission is:

/dhcpd.confThe first time you modify the configuration file tip let me refer to/usr/share/doc/dhcp*/dhcpd.conf.sample, copy a template to overwrite the original configuration file with CP/usr/share/doc/dhcp*/ dhcpd.conf.sample/etc/dhcp/dhcpd.conf Ddns-update-style none;Ignore client-updates;Subnet 192.168.10.0 netmask 255.255.255.0 {//DHCP assignment to 10 segmentsoption routers 192.168.10.1; 10 Gateway for network segmentoption Subnet-mask 255.255.255.0;//Subnet Mask#option domain-name "linux.c

and scalability, users just pay the lineStand-alone server: Customers own a single serverInstalling Apache Note that the Apache Service program's package name is httpd, so Yum will not install Apache #yum Install httpd #systemctl Start httpd #systemctl Enable Httpd.service Open the browser, enter 127.0.0.1, you can see the default page, I use ELinks650) this.width=650; "src=" Http://s3.51cto.com/wyfs02/M00/99/9F/wKioL1lKOW3yQYuyAAI4QxaydTU605.png "/> This article i

managementLN –s/usr/local/apache2/bin/apachectl/etc/init.d/apacheAllow the Apache service of the source package to be chkconfig and NTSYSV command Management self-initiatedVI /etc/init.d/apache #指定httpd脚本可以被chkconfig命令管理, format chkconfig: Run-level boot order Close Order # cannot conflict with existing script's boot order and shutdown Order # CHK Config: * Description, free content # Description:source package Apache　　　Then execute: Chkconfig–add ApacheNote: It is not recommended to do such a