Random Linux skill note (Linux Command reference)

Reprinted from: http://www.oschina.net/code/snippet_104837_22165

Tips = new array (222); Code = new array (222); Tips [0] = 'view software XXX installation content '; code [0] = 'dpkg-l XXX'; Tips [1] = 'Find software in the software warehouse '; Code [1] = 'apt-cache search regular expression '; tips [2] = 'Find the software in the software'; Code [2] = 'Aptitude search package '; Tips [3] = 'Find the package of the file '; code [3] = 'dpkg-s filename '; Tips [4] = 'Find the package of the filename File'; Code [4] = 'apt-file search filename '; tips [5] = 'query which packages the software XXX depends on '; Code [5] = 'apt-Cache depends XXX '; tips [6] = 'query which packages depend on the software XXX '; cod E [6] = 'apt-Cache rdepends XXX'; Tips [7] = 'Add a disc source'; Code [7] = 'sudo apt-CDROM add '; tips [8] = "system upgrade"; Code [8] = 'sudo apt-Get update; sudo apt-Get dist-upload '; tips [9] = "Clear the residual configuration file of the deleted package "; code [9] = "dpkg-L | grep ^ RC | awk '{print $2}' | sudo xargs dpkg-P "; tips [10] = 'automatic processing of hfile missing during compilation '; Code [10] = 'sudo auto-apt run. /configure '; Tips [11] = "view the temporary directory for storing packages downloaded during software installation"; Code [11] = "ls/var/Cache/APT/Archives "; tips [12] = "Back up the list of all packages installed in the current system"; Code [12] = "dpkg -- Get-selections | grep-V deinstall> ~ /Somefile "; Tips [13] =" recover all packages from the list file of the backup installation package "; Code [13] =" dpkg -- Set-selections <~ /Somefile; sudo dselect "; Tips [14] =" Clear Old Version Software cache "; Code [14] =" sudo apt-Get autoclean "; tips [15] = "Clear all software caches"; Code [15] = "sudo apt-Get clean"; Tips [16] = "delete isolated software that is no longer used by the system "; code [16] = "sudo apt-Get autoremove"; Tips [17] = "view the address of the package on the server "; code [17] = "apt-get-QQ -- print-Uris Install SSH | cut-d \ '-F2"; Tips [18] = "view kernel "; code [18] = "uname-a"; Tips [19] = "view Ubuntu version"; Code [19] = "cat/etc/issue or lsb_release- "; Tips [20] =" view kernel loaded modules "; Code [20] =" lsmod "; Tips [21] =" view PCI device "; code [21] = "lspci"; Tips [22] = "view USB device"; Code [22] = "lsusb-V "; tips [23] = "viewing Nic status"; Code [23] = "sudo ethtool eth0"; Tips [24] = "viewing CPU information "; code [24] = "cat/proc/cpuinfo"; Tips [25] = "display current hardware information"; Code [25] = "sudo lshw "; tips [26] = "display system running time"; Code [26] = "uptime"; Tips [27] = "view hard disk partition "; code [27] = "sudo fdisk-L"; Tips [28] = "hard disk partition"; Code [28] = "sudo Fdisk/dev/SDA "; Tips [29] =" hard disk formatting "; Code [29] =" sudo mkfs. ext3/dev/sda1 "; Tips [30] =" hard disk check (do not check the mounted partitions; otherwise, data is easily damaged )"; code [30] = "sudo fsck/dev/sda1"; Tips [31] = "partition mounting "; code [31] = "sudo Mount-T file system type (-o nls = utf8 or-O iocharset = utf8) device path access path "; tips [32] = "partition unmount"; Code [32] = "sudo umount directory name or device name"; Tips [33] = "view IDE Hard Disk information "; code [33] = "sudo hdparm-I/dev/hda"; Tips [34] = "view stat hard disk information"; Code [34] = "sudo HDP Arm-I/dev/SDA or sudo blktool/dev/SDA ID "; Tips [35] =" view remaining disk space "; Code [35] =" DF "; tips [36] = "view the space occupied by the Directory"; Code [36] = "Du-HS directory name"; Tips [37] = "the USB flash drive cannot be detached "; code [37] = "sync; Fuser-km/Media/usbdisk"; Tips [38] = "viewing the current read/write status of the hard disk "; code [38] = "sudo iostat-x 2"; Tips [39] = "view current memory usage"; Code [39] = "free "; tips [40] = "dynamically display process execution status"; Code [40] = "TOP"; Tips [41] = "view processes currently "; code [41] = "PS-a"; Tips [42] = "view current process Tree"; Code [42] = "Pstree"; Tips [43] = "abort a process"; Code [43] = "Kill process number or killall process name "; tips [44] = "Force stop a process"; Code [44] = "Kill-9 process number or killall-9 process name "; tips [45] = "stop a program in graphical mode"; Code [45] = "xkill the mouse with the skeleton sign, click the program to be aborted "; tips [46] = "viewing files opened by a process"; Code [46] = "lsof-P"; Tips [47] = "Displaying processes with opened file abc.txt "; code [47] = "lsof abc.txt"; Tips [48] = "show what programs are running on port 22"; Code [48] = "lsof-I: 22 "; tips [49] = "display the files opened by the NSD process"; Code [49] = "lsof -C nsd "; Tips [50] =" run the program in the background and do not end the program after logging out "; Code [50] =" nohup Program &"; tips [51] = "Detailed display of program running information"; Code [51] = "strace-f-o OUTFILE <cmd> "; tips [52] = "increasing the maximum number of files opened by the system"; Code [52] = "ulimit-N 4096 or ECHO 4096>/proc/sys/fs/file-Max "; tips [53] = "Configuring ADSL"; Code [53] = "sudo pppoeconf"; Tips [54] = "ADSL Manual dialing "; code [54] = "sudo Pon DSL-provider"; Tips [55] = "Activate ADSL"; Code [55] = "sudo/etc/PPP/pppoe_on_boot"; Tips [56] = "Disconnect ADSL"; Code [56] = "sudo poff"; Tips [57] = "view dialing log"; Code [57] = "sudo plog "; tips [58] = "how to set dynamic domain names"; Code [58] = "w3m-no-cookie-dump 'HTTP: // usere: pass@members.3322.org/dyndns/update? System = dyndns & hostname = yourdns.3322.org '"; Tips [59] =" querying Nic addresses by IP Address "; Code [59] =" arping IP Address "; tips [60] = "querying computer names by IP Address"; Code [60] = "nmblookup-a ip Address"; Tips [61] = "Viewing Current IP Address "; code [61] = "ifconfig eth0 | awk '/inet/{split ($2, X, \": \ "); print X [2]}'"; tips [62] = "viewing the IP address of the current Internet "; code [62] = "w3m-no-cookie-dump www.123cha.com | grep-o '[0-9] \ {1, 3 \\}\\. [0-9] \ {1, 3 \\}\\. [0-9] \ {1, 3 \\}\\. [0-9] \ {1, 3 \} '"; Tips [63] = "Check the program listening to port 80"; Code [63] = "lsof-I: 80"; Tips [64] = "view the physical address of the current nic "; code [64] = "ARP-A | awk '{print $4}'"; Tips [65] = "add a second IP address for the same nic "; code [65] = "sudo ifconfig eth0: 0 1.2.3.4 netmask 255.255.255.0"; Tips [66] = "enable network support for Nat now "; code [66] = "Echo 1 | sudo tee/proc/sys/NET/IPv4/ip_forward; sudo iptables-T nat-I postrouting-J Masquerade "; tips [67] = "view route information"; Code [67] = "netstat-Rn or sudo route-n"; t IPS [68] = "manually add a route"; Code [68] = "sudo route add-net 192.168.0.0 netmask 255.255.255.0 GW 172.16.0.1 "; tips [69] = "manually delete a route"; Code [69] = "sudo route del-net 192.168.0.0 netmask 255.255.255.0 GW 172.16.0.1 "; tips [70] = "how to modify the nic mac address"; Code [70] = "sudo ifconfig eth0 HW ether 00: AA: BB: CC: DD: EE "; tips [71] = "count the number of current IP connections"; Code [71] = "netstat-Na | grep established | awk '{print $5}' | awk-F: '{print $1}' | sor T | uniq-c | sort-r-n "; Tips [72] =" Block IPv6 "; code [72] = "Echo 'blacklist IPv6 '| sudo tee/etc/modprobe. d/blacklist-ipv6 "; Tips [73] =" view current network connection status and program "; Code [73] =" sudo netstat-atnp "; tips [74] = "viewing the current traffic of ADSL"; Code [74] = "sudo ethstatus-I ppp0"; Tips [75] = "viewing the registration and filing status of domain names "; code [75] = "whois baidu.cn"; Tips [76] = "view the Routing Status of a domain name"; Code [76] = "tracepath baidu.cn "; tips [77] = "getting an IP address from the server again"; Code [77] = "sudo DH Client "; Tips [78] =" Download website documentation "; Code [78] =" wget-r-p-NP-K http://www.xxx.com "; tips [79] = "how to download 5 Threads"; Code [79] = "Axel-N 5 http://www.xxx.com/downloadfile.zip"; Tips [80] = "add a service "; code [80] = "sudo update-rc.d service name defaults 99"; Tips [81] = "delete a service"; Code [81] = "sudo update-rc.d service name remove "; tips [82] = "temporarily restart a service"; Code [82] = "/etc/init. d/service name restart "; Tips [83] =" temporarily disable a service "; Code [83] ="/etc/init. d/service name stop "; Tips [84] =" start a service temporarily "; Code [84] ="/etc/init. d/service name start "; Tips [85] =" Add User "; Code [85] =" sudo adduser username "; Tips [86] =" delete user "; code [86] = "sudo deluser username"; Tips [87] = "Change current user password"; Code [87] = "passwd "; tips [88] = "Change User Password"; Code [88] = "sudo passwd username"; Tips [89] = "Modify user information "; code [89] = "sudo chfn userid"; Tips [90] = "how to disable an account "; code [90] = "sudo usermod-l user name or sudo passwd-l User Name"; Tips [91] = "How to enable an account"; Code [91] = "sudo usermod-u username or sudo passwd-u username"; Tips [92] = "Add User to Admin group "; code [92] = "sudo usermod-G admin-a username"; Tips [93] = "Configure which Java is used by default "; code [93] = "sudo Update-alternatives -- config Java"; Tips [94] = "terminal setting proxy"; Code [94] = "Export http_proxy = http://xx.xx.xx.xx: XXX "; tips [95] = "modifying system logon information"; Code [95] = "sudo Vim/etc/motd"; Tips [96] = "using sun's Java compiler "; code [96] = "sudo Update-Java-alternatives-s Java -6-sun "; Tips [97] =" switching Input Method engine "; Code [97] =" im-switch-c "; tips [98] = "converting the file name from GBK to utf8"; Code [98] = "convmv-r-F cp936-T utf8 -- notest -- nosmart *"; tips [99] = "converting file content from GBK to utf8"; Code [99] = "iconv-f gbk-T utf8 $ I> newfile "; tips [100] = "Convert MP3 tag encoding"; Code [100] = "sudo apt-Get install Python-mutagen; find. -INAME '*. MP3 '-execdir mid3iconv-e GBK {}\\; "; Tips [101] =" display Chinese in the console "; Code [101] =" sudo apt- Get install zhcon; zhcon -- utf8 -- DRV = VGA "; Tips [102] =" lftp logon Remote Windows Chinese FTP "; Code [102] =" lftp: ~> Set ftp: charset GBK "; Tips [103] =" pdf file garbled "; code [103] = "sudo apt-Get install xpdf-Chinese-Simplified xpdf-Chinese-traditional poppler-Data"; Tips [104] = "one screen viewing file content "; code [104] = "cat file name"; Tips [105] = "Page View File Content"; Code [105] = "more file name "; tips [106] = "controllable Page View File Content"; Code [106] = "less file name"; Tips [107] = "view part of the file content based on string matching "; code [107] = "grep string file name"; Tips [108] = "display file names containing strings"; Code [108] = "grep-l-R string path"; tip S [109] = "display file names that do not contain strings"; Code [109] = "grep-l-R string path "; tips [110] = "quickly find a file"; Code [110] = "find directory-name file name"; Tips [111] = "create two empty Files "; code [111] = "Touch file1 file2"; Tips [112] = "recursively creating some nested directories "; code [112] = "mkdir-P/tmp/xxs/DSD/EFD"; Tips [113] = "recursively deleting nested directories "; code [113] = "RM-fr/tmp/xxs"; Tips [114] = "back to the current user's home directory"; Code [114] = "CD ~ "; Tips [115] =" view the absolute path of the current directory "; Code [115] =" PWD "; tips [116] = "list all files in the current directory"; Code [116] = "ls-"; tips [117] = "file under the Mobile path and renamed"; Code [117] = "Mv path/file/New Path/new file name "; tips [118] = "copy a file or directory"; Code [118] = "CP-AV original file or original directory new file or new directory "; tips [119] = "View File Type"; Code [119] = "file FILENAME"; Tips [120] = "compare the differences between two files "; code [120] = "Diff file1 file2"; Tips [121] = "display the last six lines of the XXX file"; Code [121] = "tail-N 6 XXX "; tips [122] = "constantly display the latest content "; Code [122] =" tail-N 10-F/var/log/apache2/access. log "; Tips [123] =" view the content from the fifth row to the second row of the file "; Code [10th] =" sed-n' 5, 10p'/var/log/apache2/access. log "; Tips [124] =" query XXX commands "; Code [124] =" Apropos xxx or man-k xxx "; tips [125] = "transferring files through SSH"; Code [125] = "SCP-RP/path/filename username @ remoteip:/path "; tips [126] = "change the suffix of all files from RM to rmvb"; Code [126] = "RENAME's /. rm $ /. rmvb/'* "; Tips [127] =" replace uppercase letters in all file names with lowercase letters "; Code [127] = "RENAME 'tr/A-Z/a-z/'*"; Tips [128] = "delete a file with a special file name --help.txt "; code [128] = "RM -- --help.txt or RM. /--help.txt "; Tips [129] =" view the subdirectory of the current directory "; Code [129] =" ls-D */. or echo */. "; Tips [130] =" Move the files accessed in the last 30 days to the upper-level back directory "; Code [130] =" Find. -Type F-atime-30-exec MV {}.. /back \; "; Tips [131] =" display XXXX-containing files within one hour "; Code [131] =" Find. -Type F-mmin-60 | xargs-I grep-l XXX' {} '"; Tips [132] =" Display Shows the files in the last 2 hours to 8 hours "; Code [132] =" Find. -mmin + 120-mmin-480-exec more {}\\; "; Tips [133] =" delete files modified 30 days ago "; code [133] = "Find. -Type F-mtime + 30-mtime-3600-exec RM {}\\; "; Tips [134] =" delete files accessed 30 days ago "; code [134] = "Find. -Type F-atime + 30-atime-3600-exec RM {}\; "; Tips [135] =" delete a guest file ending with Avi or RM "; code [135] = "Find. -name '*. avi '-o-name '*. rm '-user' guest'-exec RM {}\\; "; Tips [136] = "delete files not used seven days after the end of Java and XML"; Code [136] = "find .! -Name *. Java! -Name '*. XML '-atime + 7-exec RM {}\; "; Tips [137] =" delete all. SVN directory "; Code [137] =" Find. -Name. svn-type D-exec Rm-fr {}\\; "; Tips [138] =" delete all Temporary File ending with "; Code [138] =" find.-name '*~ '-Exec RM {}\\; "; Tips [139] =" count the number of current files "; Code [139] =" ls. | WC-W "; Tips [140] =" count the number of current directories "; Code [140] =" ls-L | grep ^ d | WC-l "; tips [141] = "display the file name of in the current directory"; Code [141] = "ls-L | grep | awk '{print $8 }'"; tips [142] = "Synchronizing Remote Data to the local directory through SSH"; Code [142] = "rsync-pa-I -- size-only -- delete -- timeout = 300 remote_ip: /home/Ubuntu/backup "; Tips [143] =" added 7z compression software "; Code [143] =" sudo apt-Get instal L p7zip p7zip-full p7zip-rar "; Tips [144] =" added RAR software compression and decompression support "; Code [144] =" sudo apt-Get install RAR unrar "; tips [145] = "decompress xxx.tar.gz"; Code [145] = "Tar-zxvf xxx.tar.gz"; Tips [146] = "decompress xxx.tar.bz2 "; code [146] = "Tar-jxvf xxx.tar.bz2"; Tips [147] = "compressing AAA bbbdirectory as xxx.tar.gz"; Code [147] = "Tar-zcvf xxx.tar.gz aaa bbb "; tips [148] = "compress AAA bbbdirectory as xxx.tar.bz2"; Code [148] = "Tar-jcvf xxx.tar.bz2 AAA B Bb "; Tips [149] =" added LHA support "; Code [149] =" sudo apt-Get install LHA "; tips [150] = "added support for resolving CAB files"; Code [150] = "sudo apt-Get install cabextract"; Tips [151] = "Show Calendar "; code [151] = "Cal"; Tips [152] = "set date"; Code [152] = "date-s mm/DD/YY "; tips [153] = "Set Time"; Code [153] = "date-s hh: mm"; Tips [154] = "write time into CMOS "; code [154] = "hwclock -- systohc"; Tips [155] = "view CMOS time"; Code [155] = "hwclock -- Show"; Tips [156] = "read Obtain the CMOS time "; Code [156] =" hwclock -- hctosys "; Tips [157] =" synchronize time from the server "; Code [157] =" sudo ntpdate ntp.ubuntu.com "; tips [158] = "set the time zone of your computer to Shanghai"; Code [158] = "sudo CP/usr/share/zoneinfo/Asia/Shanghai/etc/localtime "; tips [159] = "Disable UTC and write the current time to CMOS. "; Code [159] =" sudo sed-ie's/UTC = Yes/UTC = No/G'/etc/default/RCS; sudo hwclock -- systohc "; tips [160] = "Modify MySQL Root Password"; Code [160] = "sudo mysqladmin-u root-P password 'your new password '"; tips [161] = "How to Use the command to disable the monitor"; Code [161] = "xset dpms force off"; Tips [162] = "set the CPU frequency "; code [162] = "sudo apt-Get install cpufrequtils; sudo cpufreq-Info"; Tips [163] = "command shutdown"; Code [163] = "sudo halt "; tips [164] = "shutdown now"; Code [164] = "Sudo shutdown-H now"; Tips [165] = "automatic shutdown at"; Code [165] = "sudo shutdown-h "; tips [166] = "shutdown after 60 Minutes"; Code [166] = "sudo shutdown-H + 60"; Tips [167] = "command to restart the computer "; code [167] = "sudo reboot"; Tips [168] = "restart your computer now"; Code [168] = "sudo shutdown-R now "; tips [169] = "turn off the notebook touchpad"; Code [169] = "synclient touchpadoff = 1"; Tips [170] = "turn on the notebook touchpad "; code [170] = "synclient touchpadoff = 0"; Tips [171] = "count and sort the occurrence frequency of each word "; Code [171] =" awk '{arr [$1] + = 1} end {for (I in ARR) {print arr [I] \ "\ t \" I} 'file_name | sort-RN "; Tips [172] =" count port 80 connections and sort "; code [172] = "netstat-Na | grep: 80 | awk '{print $5}' | awk-F: '{print $1}' | sort | uniq-c | sort-r-n "; Tips [173] =" add terminal to right menu "; code [173] = "sudo apt-Get install Nautilus-open-terminal"; Tips [174] = "how to delete the playback history of a totem player "; code [2, 174] = "RM ~ /. Recently-used "; Tips [175] =" how to display color characters in VIM "; code [175] = "sudo CP/usr/share/Vim/vimcurrent/vimrc_example.vim/usr/share/Vim/vimrc"; Tips [176] = "Let Vim directly support editing. GZ file "; Code [176] =" sudo apt-Get install vim-full "; Tips [177] =" How Vim displays row numbers "; Code [177] = ": set number "; Tips [178] =" view the startup program set in the session "; Code [178] =" ls ~ /. Config/autostart "; Tips [179] =" Improving wine response speed "; Code [179] =" sudo sed-Ie '/GBK /, /^}/d '/usr/share/X11/locale/zh_CN.UTF-8/xlc_locale "; Tips [180] =" create ISO file "; code [180] = "mkisofs-O test. iso-jrv-V test_disk/home/Carla/"; Tips [181] =" 10 seconds behind image capture "; Code [181] =" gnome-screenshot-D 10 "; tips [182] = "5 seconds to capture the current activation window"; Code [182] = "gnome-screenshot-w-D 5 "; tips [183] = "how to burn command lines"; Code [183] = "cdrecord-scanbus; cdre Cord-v-eject speed = 8 Dev = 184, 0 test. ISO "; Tips [184] =" where is the recycle bin "; Code [] = "~ /. Local/share/trash/"; Tips [185] =" where is the configuration file opened by default "; Code [185] = "~ /. Local/share/applications/mimeapps. list "; Tips [186] =" how to view HTTP headers "; Code [186] =" w3m-dump_head http://www.xxx.com "; Tips [187] =" continuously monitor memory usage "; code [187] = "watch-d Free"; Tips [188] = "how to switch to the root account"; Code [188] = "Sudo-HS "; tips [189] = "Read-Only mounting NTFS partitions"; Code [189] = "sudo Mount-t ntfs-o nls = utf8, umask = 0/dev/sdb1/mnt/C "; Tips [190] =" writable mounting NTFS partition "; code [190] = "sudo Mount-T ntfs-3g-O locale = zh_cn.utf8, umask = 0/ Dev/sdb1/mnt/C "; Tips [191] =" Mount FAT32 partition "; Code [191] =" sudo Mount-T vfat-O iocharset = utf8, umask = 0/dev/sda1/mnt/C "; Tips [192] =" Mount shared files "; code [192] = "sudo Mount-T smbfs-O username = xxx, password = xxx, iocharset = utf8 // 192.168.1.1/share/mnt/share "; tips [193] = "mounting ISO Files"; Code [193] = "sudo Mount-T iso9660-o loop, utf8 XXX. ISO/mnt/ISO "; Tips [194] =" content of the file displayed with a row number "; Code [194] =" NL file name "; Tips [195] =" batch RMV Convert B to Avi "; Code [195] =" for I in *; do mencoder-OAC mp3lame-lameopts VBR = 3-OVC XviD-xvidencopts fixed_quant = 4-of AVI $ I-o 'echo $ I | sed-E's/rmvb $/Avi /''; done "; Tips [196] =" Convert SVG to PNG in batches "; Code [196] =" for I in *; do inkscape $ I -- export-PNG = 'echo $ I | sed-E's/SVG $/PNG/''; done "; tips [197] = "batch scale down images to 30%"; Code [197] = "for I in *; do convert-resize 30% x30 % $1 Sm-$1; done "; Tips [198] =" batch convert JPG to P NG "; Code [198] =" for I in *; do convert $ I 'echo $ I | sed-E's/jpg $/PNG/''; done "; tips [199] = "Get JPG extension information (EXIF)"; Code [199] = "identify-verbose xxx.jpg "; tips [200] = "view all listening ports of the current system"; Code [200] = "nc-ZV localhost 1-65535 "; tips [201] = "Remove ^ m from the file"; Code [201] = "cat filename | tr-d \" ^ m \ "> newfile "; tips [202] = "Remove ^ m from the file"; Code [202] = "sed-e \" s/^ m // G \ "FILENAME> newfile "; tips [203] = "converting bin/cue to ISO Files"; Code [203] = "sudo apt-Get install bchunk; bchunk image. bin image. cue image "; Tips [204] =" converting directories to ISO Files "; Code [204] =" mkisofs dirname-O isofile. ISO "; Tips [205] =" converting CD to ISO Files "; Code [205] =" dd If =/dev/CDROM of = isofile. ISO "; Tips [206] =" ape to FLAC "; Code [206] =" sudo apt-Get install FLAC shntool; shntool split-T \ "% N. % P-% t \ "-F example_UTF-8.cue-o flac example. ape-D flacoutputdir "; Tips [207] =" ape to MP3 "; Code [207] =" sudo apt-Get install FLAC shntool lame; shntool split-T \ "% N. % P-% t \ "-F example_UTF-8.cue-O 'cust ext = MP3 lame -- r3mix-B 320 -- quiet-% f'example. ape-D mp3outputdir "; Tips [208] =" check for local security risks "; Code [208] =" sudo apt-Get install rkhunter; rkhunter -- checkall "; tips [209] = "how to install anti-virus software"; Code [209] = "sudo apt-Get install ClamAV; clamscan-R ~ /"; Tips [210] =" viewing network connection status "; code [210] = "netstat-N | awk '/^ TCP/{++ s [$ NF]} end {for (a in S) print, s [a]} '"; Tips [211] =" memory usage of the statistical program "; Code [211] =" PS-EO fname, RSS | awk '{arr [$1] + = $2} end {for (I in ARR) {print I, arr [I]} '| sort-K2-Nr "; Tips [212] =" display current memory size "; code [212] = "free-M | grep \" mem \ "| awk '{print $2 }'"; tips [213] = "process by memory from large to small"; Code [213] = "PS-EO \" % C: % P: % Z: % A \ "| sort-K5-Nr"; Tips [214] = "process by CPU utilization from large to small "; code [214] = "PS-EO \" % C: % P: % Z: % A \ "| sort-Nr "; tips [215] = "counting the size of all JPG files in the current directory"; Code [215] = "Find. -name *. jpg-exec WC-C {}\\; | awk '{print $1}' | awk '{A + = $1} end {print }'"; tips [216] = "clearing dead processes"; Code [216] = "PS-eal | awk '{if ($2 = \" Z \") {print $4} '| sudo kill-9 "; Tips [217] =" CD: MP3 (lossy )"; code [217] = "sudo apt-Get install ABCDE; ABCDE-O MP3-B"; Tips [218] = "CD: FLAC (lossless )"; code [218] = "sudo apt-Get install ABCDE; ABCDE-o flac-B"; Tips [219] = "display statistics of the system installation package "; code [219] = "apt-Cache stats"; Tips [220] = "display the names of all available system packages"; Code [220] = "apt-Cache pkgnames "; tips [221] = "show package information"; Code [221] = "apt-Cache show k3b"; Index = math. floor (math. random () * tips. length); document. write ("" + tips [Index] + ': <code>' + code [Index] + '</code> ');