Commands using head (314)

  • In OSX you would have to make sure that you "sudo -s" your way to happiness since it will give a few "Permission denied" errors before finally spitting out the results. In OSX the directory structure has to start with the "Users" Directory then it will recursively perform the operation. Your Lord and master, Mematron Show Sample Output


    1
    sudo -s du -sm /Users/* | sort -nr | head -n 10
    mematron · 2012-09-13 10:15:23 4

  • 1
    echo $(</dev/urandom tr -dc 1-6 | head -c1)
    unixmonkey40000 · 2012-09-21 08:38:51 7
  • Generate a 18 character password from character set a-zA-Z0-9 from /dev/urandom, pipe the output to Python which prints the password on standard out and in crypt sha512 form. Show Sample Output


    1
    cat /dev/urandom | tr -dc 'a-zA-Z0-9' | fold -w 18 | head -1 | python -c "import sys,crypt; stdin=sys.stdin.readline().rstrip('\n'); print stdin;print crypt.crypt(stdin)"
    cnyg · 2012-11-09 00:40:22 4
  • Replaces hexdump with the more succint xxd, and the sed was unnecessarily complex.


    1
    xxd -p /dev/urandom |fold -60|head -30|sed 's/\(..\)/\1 /g'
    psifertex · 2013-02-19 22:18:52 4

  • 1
    tr -dc 'A-Za-z0-9!@#$%^&*' < /dev/urandom | fold -w 12 | head -n 1
    opexxx · 2013-03-15 13:20:32 81
  • Interesting to see which packages are larger than the kernel package. Useful to understand which RPMs might be candidates to remove if drive space is restricted. Show Sample Output


    1
    rpm -qa --queryformat '%{size} %{name}-%{version}-%{release}\n' | sort -k 1,1 -rn | nl | head -16
    mpb · 2013-03-19 21:10:54 6

  • 1
    awk '{print $1}' ~/.bash_history | sort | uniq -c | sort -rn | head -n 10
    nesses · 2013-05-03 16:24:30 6
  • I'm not sure how reliable this command is, but it works for my needs. Here's also a variant using grep. nslookup www.example.com | grep "^Address: " | awk '{print $2}' Show Sample Output


    1
    nslookup www.example.com | tail -2 | head -1 | awk '{print $2}'
    wsams · 2013-09-05 20:26:45 11
  • Sorts by latest modified files by looking to current directory and all subdirectories Show Sample Output


    1
    find . -name '*pdf*' -print0 | xargs -0 ls -lt | head -20
    fuats · 2013-10-03 21:58:51 9

  • 1
    for i in `seq 1 4096`; do tr -dc A-Za-z0-9 </dev/urandom | head -c8192 > dummy$i.rnd; done
    BoxingOctopus · 2013-11-11 21:27:15 8
  • Using the 'time' command, running this with 'tr' took 28 seconds (and change) each time but using base64 only took 8 seconds (and change). If the file doesn't have to be viewable, pulling straight from urandom with head only took 6 seconds (and change)


    1
    for i in {1..4096}; do base64 /dev/urandom | head -c 8192 > dummy$i.rnd ; done
    pdxdoughnut · 2013-11-12 00:36:10 9
  • Download latest NVIDIA Geforce x64 Windows7-8 driver from Nvidia's website. Pulls the latest download version (which includes beta). This is the "English" version. The following command includes a 'sed' line to replace "english" with "international" if needed. You can also replace the starting subdomain with "eu." "uk." and others. Enjoy this one liner! 1 character under the max :) wget "us.download.nvidia.com$(wget -qO- "$(wget -qO- "nvidia.com/Download/processFind.aspx?psid=95&pfid=695&osid=19&lid=1&lang=en-us" | awk '/driverResults.aspx/ {print $4}' | cut -d "'" -f2 | head -n 1)" | awk '/url=/ {print $2}' | sed -e "s/english/international/" | cut -d '=' -f3 | cut -d '&' -f1)" Show Sample Output


    1
    wget "us.download.nvidia.com$(wget -qO- "$(wget -qO- "nvidia.com/Download/processFind.aspx?psid=95&pfid=695&osid=19&lid=1&lang=en-us"|awk '/driverResults.aspx/ {print $4}'|cut -d "'" -f2|head -n 1)"|awk '/url=/ {print $2}'|cut -d '=' -f3|cut -d '&' -f1)"
    lowjax · 2013-11-21 03:04:59 11
  • Specific to OSX. Show Sample Output


    1
    sysctl -a | grep boottime | head -n 1
    lgarron · 2014-01-24 13:03:48 7

  • 1
    git verify-pack -v .git/objects/pack/pack-*.idx | grep blob | sort -k3nr | head | while read s x b x; do git rev-list --all --objects | grep $s | awk '{print "'"$b"'",$0;}'; done
    qdrizh · 2014-06-25 07:37:24 6
  • Print the IP address and the Mac address in the same line Show Sample Output


    1
    ifconfig | head -n 2 | tr -d '\n' | sed -n 's/.*\(00:[^ ]*\).*\(adr:[^ ]*\).*/mac:\1 - \2/p'
    Koobiac · 2014-09-03 14:35:27 18
  • Top 30 History Command line with histogram display Show Sample Output


    1
    history|awk '{print $2}'|sort|uniq -c|sort -rn|head -30|awk '!max{max=$1;}{r="";i=s=100*$1/max;while(i-->0)r=r"#";printf "%50s %5d %s %s",$2,$1,r,"\n";}'
    injez · 2014-09-29 12:40:43 9
  • This checks the system load every second and if it's over a certain threshold (.8 in this example), it spits out the date, system loads and top 4 processes sorted by CPU. Additionally, the \a in the first echo creates an audible bell.


    1
    while sleep 1; do if [ $(echo "$(cat /proc/loadavg | cut -d' ' -f1) > .8 " | bc) -gt 0 ]; then echo -e "\n\a"$(date)" \e[5m"$(cat /proc/loadavg)"\e[0m"; ps aux --sort=-%cpu|head -n 5; fi; done
    tyzbit · 2014-12-08 15:44:40 8
  • Finds the date of the first commit in a git repository branch Show Sample Output


    1
    git rev-list --all|tail -n1|xargs git show|grep -v diff|head -n1|cut -f1-3 -d' '
    binaryten · 2015-02-04 19:35:16 11
  • I copied this (let's be honest) somewhere on internet and I just made it as a function ready to be used as alias. It shows the 10 most used commands from history. This seems to be just another "most used commands from history", but hey.. this is a function!!! :D Show Sample Output


    1
    mosth() { history | awk '{CMD[$2]++;count++;}END { for (a in CMD)print CMD[a] " " CMD[a]/count*100 "% " a;}' | grep -v "./" | column -c3 -s " " -t | sort -nr | nl | head -n10; }
    nnsense · 2015-05-11 17:41:55 19
  • Useful to identify the field number in big CSV files with large number of fields. The index is the reference to use in processing with commands like 'cut' or 'awk' involved. Show Sample Output


    1
    head -1 file.csv | tr ',' '\n' | tr -d " " | awk '{print NR,$0}'
    neomefistox · 2015-08-26 05:46:15 18

  • 1
    curl -sL http://goo.gl/3sA3iW | head -16 | tail -14
    cadejscroggins · 2015-09-19 07:19:49 10
  • You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials Show Sample Output


    1
    head -n1 | xargs -I {} aws sts get-session-token --serial-number $MFA_ID --duration-seconds 900 --token-code {} --output text --query [Credentials.AccessKeyId,Credentials.SecretAccessKey,Credentials.SessionToken]
    keymon · 2016-04-12 10:57:00 46

  • 1
    du -a /var | sort -n -r | head -n 10
    zluyuer · 2016-05-27 04:05:08 12
  • sort -R randomize the list. head -n1 takes the first.


    1
    links `lynx -dump -listonly "http://news.google.com" | grep -Eo "(http|https)://[a-zA-Z0-9./?=_-]*" | grep -v "google.com" | sort -R | uniq | head -n1`
    mogoh · 2016-07-26 12:54:53 15

  • 1
    find / -path /proc -prune -o -type f -printf '%TY-%Tm-%Td %TT %p\n' | sort -r | head -50
    sidneycrestani · 2016-11-20 02:45:01 13
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Equivalent to ifconfig -a in HPUX

Steve Reich - Piano Phase; interpreter: Bourne-Again Shell.
The Piano Phase piece, by Steve Reich is a minimalist composition which is played on two pianos played at slightly different tempos, a task that's very difficult to accomplish by human players. The auditive effects produced by the cell displacement produce beautiful patterns. See https://en.wikipedia.org/wiki/Piano_Phase . My rendered version: https://ydor.org/SteveReich/piano_phase.mp3 Requires sox to be installed on the system. There are multiple videos on youtube showing different approaches and experiences to this interpretation. There is also a synthesized version. Even if Bash can behave as a powerful pianist, a simple threaded version leaves full room to several time glitches and even negative displacements, the same issues that human pianists experience when playing the piece. The older the computer, the better the chaos added to the result due to the CPU load. Apparently that's the reason Steve Reich composes pieces such as this. Without further ado, please give a warm welcome to the Bash minimalist player on synthesized two-threaded pianos. Please turn off your cellphones.

Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

Rename files in batch

prettier
Slightly shorter to type

Rename files in batch

reclaim your window titlebars (in ubuntu lucid)

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

See system users

Open Remote Desktop (RDP) from command line and connect local resources
The above command will open a Remote Desktop connection from command line, authenticate using default username and password (great for virtual machines; in the exampe above it's administrator:password), create a shared folder between your machine and the other machine and configure resolution to best fit your desktop (I don't like full screen because it make the desktop panels to disappear). The command will run in the background, and expect to receive parameters. You should enter hostname or IP address as a parameter to the command, and can also override the defaults parameters with your own.


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