All commands (13,438)

  • Dump man page as clean text

    Dumping man pages to text typically retains certain formatting such as foo^H^H^H___ for underscoring, and reverse-line feeds (not sure why). 'col -bx' removes these. Show Sample Output


    0
    man2txt() { man "$@" | col -bx ;}
    bartonski · 2018-10-14 01:38:04 0
  • Get a diff of two json arrays

    jq is amazing for manipulating json on the commandline, but the developers have some weird ideas about how to handle shell redirections. This command works around them. Further reading: https://github.com/stedolan/jq/issues/1110


    1
    diff <(jq . -M -S < old.json) <(jq . -M -S < new.json)
    malathion · 2018-10-11 20:59:48 0
  • Create and access directory at the same time

    The previous alternative dont work (the cd command was missing).


    2
    mkdir [[folder]] && cd $_
    mlinoba · 2018-10-11 16:40:53 0
  • Continuous random string of text


    0
    while true; do sleep .15; head /dev/urandom | tr -dc A-Za-z0-9; done
    allyman17 · 2018-10-10 18:57:34 0
  • Disable updates for installed Chrome plugins

    This will allow you to ensure you don't get nagged by updates and also protects you from watering hole attacks! Please be sure to make sure your plugins don't have any security issues! Backups are manifext.jason.bak credit @Jay https://chat.counterpoint.info


    0
    find / -iname "manifest.json" -exec sed 's/\"update_url\": \"http/\"update_url\": \"hxxp/g' -i.bak '{}' \;
    operat0r · 2018-10-09 19:50:31 0
  • Create and access directory at the same time

    Create and access directory


    0
    mkdir [folder-name] && $_
    ehmuidifici · 2018-10-09 18:48:16 2
  • Toggle the Touchpad on or off


    0
    tp=$(synclient -l | grep TouchpadOff | awk '{ print $3 }') && tp=$((tp==0)) && synclient TouchpadOff=$tp
    jny · 2018-10-09 07:42:32 0
  • get all Google ipv4 subnets for a iptables firewall for example

    a bit shorter, parenthesis not needed but added for clarity Show Sample Output


    0
    nslookup -q=TXT _netblocks.google.com | grep -Eo 'ip4:([0-9\.\/]+)' | cut -d: -f2
    jseppe · 2018-10-05 18:19:15 2
  • Create a role on the Chef server with a description


    0
    knife role create role-name --description "this is a role that does cool stuff"
    niko47 · 2018-10-05 16:00:41 0
  • get all Amazon cloud (amazonws etc) ipv6 subnets


    1
    curl -s https://ip-ranges.amazonaws.com/ip-ranges.json | awk -F'"' '/ipv6_prefix/ {print $4}'
    emphazer · 2018-10-05 13:01:03 0
  • get all Amazon cloud (amazonws etc) ipv4 subnets


    1
    curl -s https://ip-ranges.amazonaws.com/ip-ranges.json | awk -F'"' '/ip_prefix/ {print $4}'
    emphazer · 2018-10-05 12:59:33 0
  • get all Google ipv4 subnets for a iptables firewall for example


    2
    nslookup -q=TXT _netblocks.google.com | grep -Po '\b([0-1]?\d{1,2}|2[0-4]\d|25[0-5])(\.([0-1]?\d{1,2}|2[0-4]\d|25[0-5])){3}(/\d{1,2})\b'
    emphazer · 2018-10-05 12:50:48 0
  • Use jq to validate and pretty-print json output

    The `jq` tool can also be used do validate json files and pretty print output: ` jq < file.json` Available on several platforms, including newer debian-based systems via `#sudo apt install jq`, mac via `brew install jq`, and from source https://stedolan.github.io/jq/download/ This alternative to the original avoids the useless use of cat Show Sample Output


    0
    jq < file.json
    malathion · 2018-10-03 18:46:46 0
  • Convert hex data to binary with a bash function (requires bash v4+ for the @^^ lowercase hex demangling)

    Use this function with bash version 4+ to convert arbitrary hexadecimal sequences to binary. If you don't have bash 4+ then modify the lowercase to uppercase demangling statement s=${@^^} to set s equal to the uppercase hex input or the bc command throws an input parser error. Show Sample Output


    0
    hex2bin () { s=${@^^}; for i in $(seq 0 1 $((${#s}-1))); do printf "%04s" `printf "ibase=16; obase=2; ${s:$i:1};\n" | bc` ; done; printf "\n"; }
    RiskNerd · 2018-10-02 22:02:33 0
  • use jq to validate and pretty-print json output

    the `jq` tool can also be used do validate json files and pretty print output `cat file.json | jq` available on several platforms, including newer debian-based systems via `#sudo apt install jq`, mac via `brew install jq`, and from source https://stedolan.github.io/jq/download/ Show Sample Output


    2
    cat file.json | jq
    daemeon · 2018-10-01 23:05:27 0
  • Close specify detached screen

    -X Send the specified command to a running screen session. -S Option to specify the screen session if you have several screen sessions running. screen -ls for listing current screens and its sessionname


    1
    screen -X -S [sessionname] quit
    FanMix · 2018-10-01 14:30:01 0
  • Kill any lingering ssh processes

    Also ignoring "sshd" server is necessary since you should not kill ssh server processes.


    0
    ps aux | grep ssh | grep -v grep | grep -v sshd | awk {'print $2'} | xargs -r kill -9
    user2390 · 2018-10-01 04:49:09 2
  • create ICO file with more than one image

    requires imagemagick. -background transparent is of course optional. Show Sample Output


    1
    convert -background transparent input.png -define icon:auto-resize=16,32,48,64,128 favicon.ico
    emphazer · 2018-09-27 13:12:03 0
  • loop files with SPACES on their names

    use '*' instead of 'ls'


    -2
    for f in *;do echo $f;done
    famaral · 2018-09-21 14:27:23 1
  • Nginx - print all optional modules before compilation

    wget http://nginx.org/download/nginx-1.15.3.tar.gz && tar -xzf 1.15.3.tar.gz && cd nginx-1.15.3 Show Sample Output


    1
    ./configure --help | grep -P "^ +--with-(?!(poll|select))[^=]+(_module( |$)| (module|support)$)" | sed -r 's/((dis|en)able|build) /# /'
    emphazer · 2018-09-14 12:54:06 0
  • urlencoding with one pure BASH builtin

    opposite of https://www.commandlinefu.com/commands/view/10014/urldecoding-with-one-pure-bash-builtin ;-) Show Sample Output


    0
    function URLEncode { local dataLength="${#1}"; local index; for ((index = 0;index < dataLength;index++)); do local char="${1:index:1}"; case $char in [a-zA-Z0-9.~_-]) printf "$char"; ;; *) printf "%%%02X" "'$char"; ;; esac; done; }
    emphazer · 2018-09-14 12:08:10 0
  • Unlock VMs in Proxmox

    Unlock your VMS to avoid problems after some failed tasks ended. Show Sample Output


    0
    for i in $(qm list | awk '{ print $1 }' | grep -v VMID); do echo "Unlocking:" $i; qm unlock $i; echo "Unlocked"; done
    arkalira · 2018-09-13 08:35:12 0
  • Print the 16 most recent RPM packages installed in newest to oldest order


    1
    rpm -qa --last | head -n 16
    sparsile · 2018-09-13 02:55:51 0
  • Print the 16 most recent RPM packages installed in newest to oldest order

    Display a list of the 16 most recently installed RPM packages with newest first. Show Sample Output


    0
    rpm -qa --queryformat '%{INSTALLTIME} %{name}-%{version}-%{release}\n' | sort -k 1,1 -rn | nl | head -16 | awk '{printf("%3d %s %s\n", $1,strftime("%c",$2),$3)}'
    mpb · 2018-09-12 17:47:26 1
  • See entire packet payload using tcpdump.


    1
    tcpdump -nnvvXSs 1514 -i <device> <filters>
    25killer · 2018-09-09 10:37:19 0
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To have only unique lines in a file

backup directory. (for bash)

Get all IPs via ifconfig

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Record live sound in Vorbis (eg for bootlegs or to take audio notes)
This will record the capture channel of your soundcard, directly encoded in Ogg Vorbis, in stereo at quality 5 (I'm using this to record live jam sessions from my line input). You can choose which device to capture (eg. line input, microphone or PCM output) with $ alsamixer -V capture You can do the same thing and live encode in MP3 or FLAC if you wish, just check FLAC and LAME man pages.

Factorial With Case
Computes factorials.

grep certain file types recursively

Follow the most recently updated log files
This command finds the 5 (-n5) most frequently updated logs in /var/log, and then does a multifile tail follow of those log files. Alternately, you can do this to follow a specific list of log files: sudo tail -n0 -f /var/log/{messages,secure,cron,cups/error_log}

Inverted cowsay
It's quite fun to invert text using "flip.pl" (ref: http://ubuntuforums.org/showthread.php?t=2078323 ). Slightly more challenging is to flip a whole "cowsay". :-)

Use lynx to run repeating website actions
This command will tell lynx to read keystrokes from the specified file - which can be used in a cronjob to auto-login on websites that give you points for logging in once a day *cough cough* (which is why I used -accept_all_cookies). For creating your keystroke file, use: $ lynx -cmd_log yourfile

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