Big Data Daily Dry day fourth (Linux Foundation one directory structure and common commands)

        in order to and QQ space synchronization, also write the fourth day, the front days will be released tomorrow, it was intended to take a day to learn something to record, through a friend to give the proposal to send words slightly systematized, from Big Data need Linux Foundation, To offline data analysis including Hadoop, Hive, Flume, HBase, and so on, to real-time data analysis including Storm, Kafka, Redias, and so on, the last part of the memory calculation includes Scala, spark, machine learning, so that the gradual, systematic learning.      linux Basic section will be shared in a few days, the main explanation today is the introduction of Linux, directory agencies and common commands.      1.linux Introduction      llinux is a free and open source operating system with many different Linux versions, but they all use the Linux kernel.                    These are different versions of Linux, with the largest number of Redhat or CentOS applications in the enterprise , Redhat and CentOS are not very different, and CentOS's exclusive yum command supports online upgrades to update the system instantly, unlike Redhat, which requires money to purchase support services. Post-Learning uses the CentOS version. Here I do not explain the specific installation of CentOS, the specific installation to the Internet casually search, a lot, according to their own number of system to download and install. CentOS Official website: http://www.centos.org/, self-download installation     2.LINUX directory structure                WHERE:   /: Root     bin   (binaries) holds binary executables     sbin   (Super use R binaries) holds binary executables, only root can access     etc (etcetera) to store system configuration files, such as environment variable/etc/profile, to configure global variables.     usr   (Unix shared reSources) is used to store shared system resources, like files shared by window LAN     Home store user files root directory     root   Super User directory     Dev ( devices) for storing device files     lib   (library) the shared libraries and kernel modules required to store and run programs in the file system     MNT   (Mount) System administrator installs temporary file system installation point     boot holds various files used for system boot     TMP   (temporary) for storing various temporary files     var   (variable) is used to store files     3 that need to change data at run time. Common commands     Linux classifications There are two types of internal commands, one is an external command:    * * Internal command: Part of the shell parser, such as cd,pwd        View Help document:        help+ command     * External commands: Programs that are outside of the shell parser, such as mkdir,cp,ls        View Help documents:        man+ commands    & nbsp;    View is internal or external command: type+ command         Use some examples to introduce Linux common commands     (1) into the user root directory     CD ~ or cd    (2) View current directory     pwd    (3) go to Lulu user root     CD ~lulu  & nbsp (4) Return to original directory      CD-    (5) go back to the top level directory      CD.     (6) View all files in the root directory, including hidden files      ls-la    (7) Create a Lulu folder in the root directory       mkdir/lulu      (8) Create SRC and webapp two directories in the/lulu directory       Create:mkdir/lulu/src             mkdir/lulu/webapp      Create mkdir/liulu/{src,webapp}    &NBSP ;(9) Go to the/lulu directory and create the. Classpath and myfile files       respectively: Touch .classpath          & nbsp Touch  myfile      Create simultaneously: Touch {.classpath,myfile}      (10) Create a a.txt in the/lulu directory with the content "Hello World"       echo "Hello World" >a.txt      Add write "Nihao"     &nbsp to myfile files ; echo "Nihao" >>myfile      note:     ;: writes content to a file, overwriting previous       >> : Append content to file, not overwrite previously, add       (11) Append a.txt content to myfile       Cat a.txt>>myfile      (12) Copy all files in/lulu directory to/LULU-BAK&NBsp         Cp-r/lulu/lulu-bak      (13) Enter the/lulu-bak directory, move a.txt to the SRC directory, and modify the file name to a.java& nbsp         MV A.txt src/a.java      (14) Delete all XML type files           RM- RF *.xml      (15) count the number of words in the myfile file           wc-w myfile          Statistics myfile file line           wc-l myfile      (16) package/lulu directory in gzip compression         Step through: TAR-CVF Lulu.tar lulu                 gzip lulu.tar        One-step completion: TAR-ZCVF lulu.tar.gz lulu      (17) Unzip it, cancel package       TAR-ZXVF Lulu .tar.gz      where:      Z: Whether you have the gzip attribute at the same time, that is, gzip compression or decompression is required. The general format is xx.tar.gz or XX. tgz      C: Create a new profile. Select this option if the user wants to back up a directory or some files. Equivalent to packaging.       x: Release files from archive       V: Show files during compression      F: Use file name       J: Whether you have bzip2 properties at the same time, i.e. whether you need to compress or decompress with bzip2. General format is xx.tar.bz2             (18) Extract/lulu.tar.bz2 to/usr below         TAR-JXVF itcast.tar.bz2-c/usr/      &NB Sp Where-C: Represents the extract to the specified directory                 Today content is written here, more content please add QQ Group to communicate and learn common progress: + 591102735

Big Data Daily Dry day fourth (Linux Foundation one directory structure and common commands)