Commands by emphazer (25)

  • urldecode with AWK

    Fast and simple awk urldecoder! Note: Parameter -n is specific to GNU awk Show Sample Output


    2
    awk -niord '{printf RT?$0chr("0x"substr(RT,2)):$0}' RS=%..
    emphazer · 2023-03-30 15:05:58 318
  • Listen to a song from youtube with youtube-dl and mpv

    Explanation Firstly the function checks if user gave it any input, and notifies the user if they failed to do so. If user has inputed a search string, the function will call upon youtube-dl to find url of the audio of the first matching youtube video and play that with mpv. Call function by wrapping search string in quotes: listen-to-yt "sultans of swing" You have to paste the line in your .zshrc and source .zshrc for it to work. Limitations The dependancies are youtube-dl and mpv. this oneliner is stolen from http://www.bashoneliners.com/oneliners/302/


    1
    listen-to-yt() { if [[ -z "$1" ]]; then echo "Enter a search string!"; else mpv "$(youtube-dl --default-search 'ytsearch1:' \"$1\" --get-url | tail -1)"; fi }
    emphazer · 2019-12-18 14:22:12 75
  • get all Google ipv4/6 subnets for a iptables firewall for example (updated version)

    google has added 2 more netblocks... Show Sample Output


    4
    for NETBLOCK in $(echo _netblocks.google.com _netblocks2.google.com _netblocks3.google.com); do nslookup -q=TXT $NETBLOCK ; done | tr " " "\n" | grep ^ip[46]: | cut -d: -f2- | sort
    emphazer · 2019-12-16 07:09:12 288
  • shuffle lines via perl


    0
    seq 1 9 | perl -MList::Util=shuffle -e 'print shuffle <>;'
    emphazer · 2019-07-03 09:39:08 38
  • blktrace - generate traces of the i/o traffic on block devices

    blktrace is a block layer IO tracing mechanism which provide detailed information about request queue operations up to user space. blkparse will combine streams of events for various devices on various CPUs, and produce a formatted output the the event information. It take the output of above tool blktrace and convert those information into fency readable form. Show Sample Output


    1
    sudo blktrace -d /dev/sda -o - | blkparse -i -
    emphazer · 2019-07-02 06:13:58 39
  • Scan all open ports without any required program


    7
    for i in {1..65535}; do (echo < /dev/tcp/127.0.0.1/$i) &>/dev/null && printf "\n[+] Open Port at\n: \t%d\n" "$i" || printf "."; done
    emphazer · 2019-05-21 09:34:15 51
  • Get Your IP Geographic Location with curl and jq


    7
    curl -s https://ipvigilante.com/$(curl -s https://ipinfo.io/ip) | jq '.data.latitude, .data.longitude, .data.city_name, .data.country_name'
    emphazer · 2019-04-26 09:15:00 48
  • 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 13:01:03 383
  • 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 12:59:33 367
  • 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 12:50:48 381
  • 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 13:12:03 341
  • 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 12:54:06 346
  • urlencoding with one pure BASH builtin

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


    2
    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 12:08:10 356
  • sleep for 1/10s or 1/100s or even 1/1000000s

    sleep in microseconds instead of seconds Alternatively to usleep, which is not defined in POSIX 2008 (though it was defined up to POSIX 2004, and it is evidently available on Linux and other platforms with a history of POSIX compliance), the POSIX 2008 standard defines nanosleep Show Sample Output


    1
    time usleep 100000
    emphazer · 2018-09-06 10:28:26 329
  • give a binary the ability to open ports below 1024 as non root user

    Binding a server to privileged port on Linux w/o running as root This is applicable to any service using privileged ports (< 1024), for instance to run a HTTP server on port 80 or a LDAP directory server on port 389 for example. Show Sample Output


    4
    sudo setcap CAP_NET_BIND_SERVICE=+eip /usr/bin/python2.7
    emphazer · 2018-09-04 17:30:47 324
  • create /dev/null if accidentally deleted or for a chroot

    Show Sample Output


    0
    mknod -m 0666 /dev/null c 1 3
    emphazer · 2018-08-16 12:10:16 319
  • convert Decimal to IP from stdin

    https://stackoverflow.com/questions/10768160/ip-address-converter Show Sample Output


    1
    awk {'print rshift(and($1, 0xFF000000), 24) "." rshift(and($1, 0x00FF0000), 16) "." rshift(and($1, 0x0000FF00), 8) "." and($1, 0x000000FF)'}
    emphazer · 2018-08-16 11:46:26 349
  • Parallel Apache Benchmark

    (echo "https://example.com/"; echo "https://example.com/"; echo "https://example.com/"; echo "https://example.com/") | parallel -k 'ab -n 10000 -c 15 {}'


    0
    cat url_list.txt | parallel -k 'ab -n 10000 -c 15 {}'
    emphazer · 2018-05-17 11:23:28 203
  • small CPU benchmark with PI, bc and time.

    # 4 cores with 2500 pi digits CPUBENCH 4 2500 . every core will use 100% cpu and you can see how fast they calculate it. if you do 50000 digitits and more it can take hours or days Show Sample Output


    1
    CPUBENCH() { local CPU="${1:-1}"; local SCALE="${2:-5000}"; { for LOOP in `seq 1 $CPU`; do { time echo "scale=${SCALE}; 4*a(1)" | bc -l -q | grep -v ^"[0-9]" & } ; done }; echo "Cores: $CPU"; echo "Digit: $SCALE" ;}
    emphazer · 2018-05-14 17:30:37 192
  • find and reduce 8x parallel the size of JPG images without loosing quality via jpegoptim


    2
    find /var/www/ -type f -name '*.[jJ][pP][gG]' -print0 | xargs -n 1 -P 8 -0 jpegoptim --strip-all --preserve --preserve-perms --quiet
    emphazer · 2018-05-14 16:39:21 160
  • find and reduce 8x parallel the size of PNG images without loosing quality via optipng


    1
    find /var/www/ -type f -name '*.[pP][nN][gG]' -print0 | xargs -L 1 -n 1 -P 8 -0 optipng -preserve -quiet -o7 -f4 -strip all
    emphazer · 2018-05-14 16:38:11 157
  • Blackhole any level zones via dnsmasq

    Explanation It creates dnsmasq-com-blackhole.conf file with one line to route all domains of com zones to 0.0.0.0 You might use "address=/home.lab/127.0.0.1" to point allpossiblesubdomains.home.lab to your localhost or some other IP in a cloud. Show Sample Output


    1
    echo "address=/com/0.0.0.0" | sudo tee /etc/dnsmasq.d/dnsmasq-com-blackhole.conf && sudo systemctl restart dnsmasq
    emphazer · 2018-05-14 16:28:18 158
  • Show all files sorted by date

    a quick function for searching changed files. just copy it in the bash Show Sample Output


    0
    FINDDATE() { LOCATION="${1:-.}"; find ${LOCATION} -type f -print0 | xargs -0 stat -c "%y %n" | sort | sed 's/.\([0-9]\)\{9,\} +0[1-2]00/\t/' | sed 's/ /\t/g' }
    emphazer · 2018-05-14 14:27:41 158
  • Calculates the number of physical cores considering HyperThreading in AWK

    Check whether hyperthreading is enabled or not. a better solution as nproc should work on all OS with awk Show Sample Output


    2
    awk -F: '/^core id/ && !P[$2] { CORES++; P[$2]=1 }; /^physical id/ && !N[$2] { CPUs++; N[$2]=1 }; END { print CPUs*CORES }' /proc/cpuinfo
    emphazer · 2018-05-14 14:17:33 155
  • find with high precission (nanoseconds 1/1,000,000,000s) the last changed file.

    this is good for variables if you have many script created files and if you want to know which one is the last created/changed one..


    1
    find . -type f -print0 | xargs -0 stat -c '%y %n' | sort -n -k 1,1 | awk 'END{print $NF}'
    emphazer · 2018-05-14 08:47:41 154

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convert flac to mp3
if you haven't already done so, install lame and flac: sudo apt-get install lame flac

Reset terminal that has been buggered by binary input or similar

Check for Firewall Blockage.
This is just one method of checking to see if an IP is blocked via IP tables or CSF. Simple and to the point. Replace xx.xx.xx.xx with the IP you wish to check.

Get your current Public IP

Rename .JPG to .jpg recursively
Recursively rename .JPG to .jpg using standard find and mv. It's generally better to use a standard tool if doing so is not much more difficult.

Revert all modified files in an SVN repo

list block devices
Shows all block devices in a tree with descruptions of what they are.

convert UNIX timestamp to UTC timestamp
date -ud @1320198157

Randomize lines in a file
shuf is in the coreutils package

get all pdf and zips from a website using wget
If the site uses https, use: $ wget --reject html,htm --accept pdf,zip -rl1 --no-check-certificate https-url

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