Linux frequently used commands

shell terminal

  • !! the previous command (Actually the latest command list with command history)
    !-1 is equal to !!
    !-2 is second command list with command history
    !^ first parameter
    !:1 first parameter
    !:n the n parameter
    !:$ last parameter

  • C-A/E jump to the head/end position
    C-U/K trim to head/tail
    C-P/N prev/next command
    C-R history command
    C-- zoom in
    C-L clear screen, same as clear
    C-C cancel current command
    C-& cancel modify
    C-T switch
    C-Y paste
    C-W delete a word
    Below operation need to unset Enable menu access keys option of terminal.
    C-f/b move cursor forward/backward a character
    M-f/b move cursor forward/backward a word
    C-d delete a character forward
    C-h delete a character backward
    M-d delete a word froward
    C-M-h delete a word backward, the word was splited by any special symbols
    C-w delete a word backward, the word was splited by space symbol only
    C-] search character forward
    C-M-] search character backward

  • <alt>+. get the last parameter of previous command

common command

  • cd - switch to last dir
    cd switch to user home dir

  • cp filename{,.bak} a fast method to bakup a file

  • mv filename{.bak,} a fast method to cut the suffix

  • time command count the elapsed time

  • mount -t cifs -o username=***,passwd=*** //ip/path /mnt/test
    mount network sharing dir
    mount -t iso9660 /mnt/iso/FC17-DVD.iso /mnt/dvd
    use for mounting ISO file
    mount --bind /root/project/myprj /root/x86_64_build/source
    mount a dir to another, use for across-compilation mostly
    mount -t tmpfs -o size=1024m tmpfs /mnt/ram
    mount memory as a w/r dir (use for high speed I/O operation, and disk space not enough)

  • tar xvf example.tar.gz -C /root/test extract files to specific dir
    tar tvf example.tar.gz list the contents of an archive
    tar -zcvf - stuff | openssl des3 -salt -k *** | dd of=stuff.des3 encryption
    tar cvfz chenxu.tar.gz dir --exclude dir/dir1 --exclude dir/dir2/dir3
    tar -xvf 1425279081.tar.gz var/log/message get only one file
    dd if=stuff.des3 | openssl des3 -d -k *** | tar zxf - decryption
    7z a -t7z -ptestpsw123 mytest.7z -r testfolder/* zip folder and encrypt it by 7z

  • getconf LONG_BIT print the operator system bits
    grep -c "lm" /proc/cpuinfo if output is not 0, it is 64bit cpu

  • du -sh
    du -s * |sort -n |tail

  • free bg kill pid killall proc chmod 777 (r:4,w:2,x:1)(user,group,all)

  • find / -name "***"
    find path \( -name "*.h" -or -name "*.c" \) -exec grep -in "***" {} \;
    find ./ -name "*.*" -exec ls -l {} \; |awk '{print $5,$9}' |sort -n |tail find the 10 biggest files.
    find / -type d -name "gedit" search direactorys
    find . \( -path ./.git -o -path dir2 \) -prune -o -type d -print search sub-dir, except .git and dir2
    find /usr/include/ -path /usr/include/boost -prune -o -name '*.h' -print >1.txt
    find . -name ".svn" | xargs rm -rf find .svn folder in current directory, and remove it.
    find ./ \( -name "*.h" -or -name "*.c" \) -exec wc -l {} \; | awk '{s+=$1} END {print s}' count lines of specify files
    find ./ \( -name "*.h" -or -name "*.c" \) | xargs wc -l | tail -n 1 count lines of specify files
    the upon two command can count lines of specify files, but what is the
    difference of them, look this
    Difference xargs and exec
    you will find the answer.
    find ./ -path ./perl -prune -o -name "*.so" -exec cp {} ../net-snmp-5.4.4-sdk/lib/ \;
    copy files which search by find, search exclude ./perl path
    find /usr -size +100M find file size larger than 100M
    find /home -mtime +120
    find /var \! -atime -90
    find <dir> -executable -type f only find executable files

  • grep -r "abc" /root/source
    grep -r --include "*.h" "date" path
    grep -m 1 "model name" /proc/cpuinfo only display the first match line
    grep -i -E "abc|123" match abc or 123, -i ignore, -E extended regular expression.
    grep -r -l "main" . search all files under each directory, -l files-with-match, -L files-withou-match
    grep -w "linux" *.md match word
    grep -rl --include=*.{h,cpp} "socket" . search socket only with .h .cpp files
    grep --exclude-dir="_posts" --exclude-dir="_site" -r "Dennis" ./ exclude specify directory
    grep -rni '[^a-zA-Z]abc[^a-zA-Z]' ./ match like “”, not match like “ttabccd”

  • cut -d"" -f1
    [root@localhost ~]# sensors |grep "Core "
    Core 0: +30.0°C (high = +76.0°C, crit = +100.0°C)
    Core 1: +37.0°C (high = +76.0°C, crit = +100.0°C)
    [root@localhost ~]# sensors |grep "Core " |cut -d"+" -f2 |cut -d" " -f1

  • history|awk '{print $2}'|awk 'begin {FS="|"} {print $1}'|sort|uniq -c|sort -rn|head -10

  • ps aux | sort -nk +4 | tail
    ps -eo pid,lstart,etime | grep 3208 view the start and running time of specify process.
    ps axjf print process tree
    ps -ef see every process
    ps -eLf get about thread info
    ps -U root -u root u see every process running as root
    pgrep firefox print the procee id of firefox

  • uname -a

  • whereis cp
    rpm -qf /usr/bin/cp
    rpm -ivp ***.rpm

  • rpm -qpl packetname list files
    rpm -i --relocate change install directory
    rpm -qa |grep XXX check whether XXX was installed
    rpm -e $(rpm -qf $(which teamviewer)) remove software

  • mkdir -p /test/dir1/dir2/dir3

  • ftp 2121
    pwd view remote directory
    lcd change to the local directory
    !ls list local files
    put 1.jpg
    get 2.jpg
    mput *.jpg
    mget *.jpgdownload multiple files

  • wget ftp://IP:PORT/* --ftp-user=xxx --ftp-password=xxx -r support download
    multiple files and directories, good to replace ftp

awk and sed

  • awk
    awk FS'' 'condition1{operator1}condition2{operator2}...' filename
    NR:number row, NF:number field
    awk 'NR==1{print $0}'
    arr=($(awk -F'#' '{print $1,$2,$3,$4}' $conf_file))
    ps aux | awk 'NR==1{print $0}$3>10{print $0}'
    awk -F'<|>' '{if(NF>3){print $2 ":" $3}}' /tmp/test.xml parse xml file
    awk -F'=' '/HWADDR/{print $2}' /etc/sysconfig/network-scripts/ifcfg-eth0

  • sed
    sed [options] 'command' file(s)
    sed [options] -f scriptfile file(s)
    sed -i '/'$prj'/{s/\(.*#.*#\)[0-9]\+/\1'$rev_new'/}' $conf_file
    sed -n 10,23p filepath -n print the specific lines
    sed 'N;s/\n/ /' filepath join two line into one
    echo -e "11\n22\n33\n" | sed -n '/22/{n;p}' print next line after match
    sed ':a;N;s/\n/ /;ba;' file join all lines

git and svn

  • git
    git clone url
    git add .
    git commit -m "***"
    git commit file -m "***"
    git push origin master
    git status
    git diff
    git rm *** remove file
    git rm -r *** remove directory
    git pull
    git mv *** ###
    git remote -v show remote repository info
    git reset <file> undo git add
    git checkout HEAD /path/file undo git rm on one file
    git rm $(git ls-files --deleted) undo git rm multiple files

  • svn
    svn list url
    svn co url
    svn status
    svn update
    svn info url
    svn di
    svn di -r ver1:ver2
    svn di -r ver1:ver2 path
    svn revert [-R] path
    svn merge -r ver2:ver1 path
    svn log -r ver1:ver2
    svn log -l5 show 5 latest logs
    svn add path
    svn commit -m "***"
    svn ci path -m "***"
    ls ~/.subversion/auth/svn.simple user information location


  • ip addr
    cat /sys/class/net/eth{0,1}/address display mac address
    ip addr add dev eth1
  • ifconfig eth0 down; ifconfig eth0 hw ether MAC_ADDR; ifconfig eth0 up change MAC address
    ifconfig eth2 netmask up add ip address for eth2
    ifconfig eth2:1 netmask up add another ip for eth2
    ifconfig eth0 mtu 6000 set MTU
  • ping -I set source address to specified interface address
  • route add default gw eth2
    route del default gw eth2
    route add -host dev eth0
    route del -host dev eth0
    route add -net gw eth2
    route del -net netmask dev eth0
    ip route flush cache
  • python -m SimpleHTTPServer
    python -m http.server for windows
  • ssh root@
  • ssh -f -NC -D7070 ssh tunnel
    ssh -f -NC -D7070 user@ ssh tunnel
  • scp root@ upload file
    scp root@ /root/mytest download file
    sshpass -p passwd scp root@
  • nmap ip
    nmap -p 8000 check the port is open or not
    nmap -v -sn
    nmap -v -sn |grep 'report' |grep -v 'down' |awk '{print $NF}' scan local alive ip
  • nc -z -w 1 IP PORT
    nc -z -w 1 100
    nc -z -w 1 -u 100
    nc -z -w 1 1-65535 scan all ports from 1 to 65535
  • lsof -i:111
    netstat -apn | grep 111
    iptables -L list rules
    iptables -L INPUT --line-numbers
    iptables -A INPUT -p tcp --dport 111 -j DROP forbid specific port
    iptables -A OUTPUT -p tcp --dport 111 -j DROP
    iptables -A INPUT -p tcp --dport 8024 -j ACCEPT all rule, allow port 8024
    iptables -I INPUT 5 -p tcp --dport 8024 -j ACCEPT add rule to specify position(5)
    iptables -D INPUT -p tcp --dport 8024 -j ACCEPT delete rule
    service iptables save
    service iptables stop
    service iptables start
  • curl
    curl get geographic location of an IP address
  • geoiplookup IP_ADDRESS
  • dig domain dig -x host
  • netstat -nlp view service and listen ports
    netstat -npt view tcp connections
    netstat -s display networking statistics
  • wget url download file
    wget -m -p -np -k -E http://site/path/ mirror the site
    wget -A pdf,jpg -m -p -np -k -E http://site/path/ only download pdf and jpg file
    wget url_file -O new_name.file rename
  • tcpdump -D list available device(run as root)
    tcpdump -i p4p1 host and port 80 -n use specify interface “p4p1”
    tcpdump -i p4p1 host and port 3260 -w tcpdump.pcap
    tcpdump -l | tee dat
    tcpdump -U host and port 3260 -w tcpdump.pcap flush each packet to packet-buffered
    tcpdump host and \ ( or \)
    tcpdump -i eth0 src host hostname
    tcpdump -i eth0 dst host hostname
    tcpdump -n -e -i eth0 icmp
    tcpdump -n -e icmp
    tcpdump -n -e arp
  • telnet 3128 check port is available or not
  • arp -a
  • squid -CNd1
  • traceroute display all the route from my host to the website


  • Fedora
    Alt+Tab switch windows
    Alt+` switch sub-windows
    Win windows key, use to show all application
    Win -> Space , search application
  • yum use local repository
    • mount iso file to /mnt/cdrom
    • modify /etc/yum.repos.d/CentOS-Media.repo, add text “file:///mnt/cdrom/“
      name=CentOS-$releasever - Media
  • yum install XXX -y
    yum search XXX
    yum remove XXX
    yum clean all
    yum makecache
  • Ubuntu
    reset root password, press ‘e’ to edit grub boot option, change ‘ro quiet splash’
    to ‘rw init=/bin/bash’, then login terminal with root, use ‘passwd’ to reset.
  • Ubuntu remove software
    • dpkg –get-selections | grep ‘software-name’
    • sudo apt-get remove –purge software_name
    • dpkg -l |grep ^rc|awk ‘{print $2}’ |sudo xargs dpkg -P

vimperator(Firfox plugin)

  • vimperator
    :help Open help page
    :helpall Show all help on one page
    C-[ cancel command mode
    d close current page
    u undo close current page
    / search
    H Go back in the browser history
    gg Go to the top of the page
    G Go to the bottom of the page
    C-f forward page
    C-b backward page
    y Copy the current URL to clipboad
    p Open the URL from current clipboad contents in current buffer
    P Open the URL from current clipboad contents in a new tab buffer
    r Reload current page
    ZZ Quit and save the session
    C-n Go to the next buffer
    C-p Go to the previous buffer
    gi Go to input field
    g-u Go to the parent directory
    g-U Go to the root of the website
    c Start caret mode.Like normal mode of vim, use h j k l to move, and
    press v to start visual mode, then press y to copy select text
    gi Use [count]gi to Focus to the [count]th input field
    C-l Go to URL editor and select it
    C-t Open a new tab


  • man 2 sys_call_name view system call function description
    man 2 open, man 2 read, man 2 write, man 2 fork
    man 3 errno view error number description
    man 3 printf
    man ascii


  • vimdiff a.log b.log diff two files
    vim -b file edit binary file, use :%!xxd and :%!xxd -r
  • diff /tmp/test01 /tmp/test02 compare file in two directory
    diff -r /tmp/test01 /tmp/test02 compare file in directory and subdirectory
    diff /tmp/test01/1.c /tmp/test02/2.c compare two files
  • patch
    diff a.c b.c > c.patch
    patch a.c c.patch
  • vmstat iostat ifstat nload top hexdump od
    hexdump -C filename display hex+ASCII of file
    iostat -x 2 5
    ipcs show all ipc info
    nload monitor network traffic, use tab key to switch to next interface, and q to quit.
  • dd if=/dev/zero of=$test_file bs=1M count=$dev_size 2>> $log
    dd of=/dev/sdh of=/dev/zero bs=1M count=500 oflag=direct test the real hard disk speed
    dd if=path/Fedora-os.iso of=/dev/sdb install fedora live os to U disk(make
    sure the mount directory of U disk is /dev/sdb, if not should change the out file directory)
  • > file.txt
  • watch -n 5 command
  • chroot .
  • date "+%F %R:%S"
    date "+%y%m%d%H%M%S"
    date +%s print timestamp of current time
    date -d @1420210697 translate timestamp to datetime
    date +%s -d"Jan 1, 1970 00:00:01" translate datetime to timestamp
  • which executefile print directory of executefile
    ldd /usr/bin/executefile print shared library dependencies
    nm /usr/lib64/ print interface
  • cat /proc/uptime | awk -F. '{d=($1/86400);h=($1%86400)/3600;m=($1%3600)/60;s=($1%60);printf("system had run %d day %d hours %d mins %d secs\n",d,h,m,s)}'
  • fuser -u /home
    fuser -v -n tcp 7070
  • echo 1 > /proc/sys/kernel/sysrq enable sysrq
    echo "b" > /proc/sysrq-trigger reboot
    echo "o" > /proc/sysrq-trigger shutdown
    shutdown -h now shutdown
    shutdown -h +10 shutdown 10 minutes later
    shutdown -h 10:00 shutdown at ten clock
  • dmidecode | more : view mainboard info
    cat /proc/cpuinfo : view CPU info
    cat /proc/pci : view pci info
    lspci : view PCI info
    cat /proc/meminfo : view memory info
    fdisk -l : view disk info
    df : view disk space useage
    cat /proc/interrupts: view interrupt request
    dmesg | more : view device debug message
  • pdftk *.pdf cat output onelargepdfile.pdf merge pdf to one
    pdftk test.pdf cat 1-3 6-20 22-end output net.pdf cut page 4,5,21 from file
    qpdf --password=1234 --decrypt encrypted.pdf decrypted.pdf decrypt pdf file
    qpdf --decrypt encrypted.pdf decrypted.pdf for empty password
  • vi -e -s -c ":%s/pattern/string/g" -c ":wq" file execute vi comand in shell
  • format u disk
    fdisk -l : find u disk
    umount /dev/sdb1 : umount u disk
    mkfs.vfat /dev/sdb1 : format as fat
  • history -c clean
    history -d offset delete specify command
  • convert -resize 1024x768 input.svg output.png convert svg to png
    convert file.pdf file.png convert pdf to images(file-XX.png)
    convert *.png file.pdf convert images to one pdf
    convert -fill green -pointsize 40 -draw 'text 10,50 "funny day"' foo.png comment.png add text to picture
  • import foo.png capture a select rectangular
  • for i inls; do mv -f $iecho $i | sed ‘s/^………/iscsi/‘; done rename
    files, replace the first 5 characters with iscsi
  • fc-list list fonts
  • strace -o 1.log -s 1024 -T -tt -p 1234 print the system call and time used for process 1234
  • printf format and print data
    printf '%x\n' 1550 convert octal value 1550 to hex, output 60e
    printf '%d\n' 0x99 convert hex value 0x99 to octal, output 153
  • echo "51200000/64/3“ |bc -l calculate
  • echo 'abc 123dd 3xxx tt' |tr -s '[:space:]' '\n' translate spaces to be line break symbol
    echo 'abc 123dT 3xXX tt' |tr '[:upper:]' '[:lower:]'
    cat |tr -s '[:space:]' '\n' |tr '[:upper:]' '[:lower:]' |sort |uniq -c| sort -nr |head -10
    find the top hot words for text document.
  • zip -Phq.hzy.zf.xf.hx.l@123 test zip “test” file to be using password
    unzip -Phq.hzy.zf.xf.hx.l@123 unzip zip file with password
    unzip -Z unzip file without password
    cat* > merge zip files
  • pkill -9 -t pts/1
  • setenforce 0 forbid Selinux temporary
    sed -i 's/SELINUX=.*/SELINUX=disabled/g' /etc/selinux/config forbid Selinux, need reboot
  • kill PID
    kill -9 PID
    kill -kill PID
  • vgchange -ay
  • lsof |grep '/core/messages' find which application open the specify file
  • for x inseq 1 1 10; do ps -eo state,pid,cmd | grep "^D"; echo "----"; sleep 5; done
    print the processes in a “D” state every 5 seconds for 10 intervals
  • echo export LANG=en_US.utf8 >>~/.profile, set lang for os, and checking with echo $LANG or locale
  • gstack threadID
  • rm !(*.pdf) remove files except pdf
  • [! -d /temp/test] && mkdir /tmp/test if folder not exist, create it.