Commands by emphazer (25)

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


    1
    awk -niord '{printf RT?$0chr("0x"substr(RT,2)):$0}' RS=%..
    emphazer · 2023-03-30 15:05:58 315
  • 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 69
  • 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 07:09:12 261

  • 0
    seq 1 9 | perl -MList::Util=shuffle -e 'print shuffle <>;'
    emphazer · 2019-07-03 09:39:08 38
  • 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

  • 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 49

  • 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 46

  • 1
    curl -s https://ip-ranges.amazonaws.com/ip-ranges.json | awk -F'"' '/ipv6_prefix/ {print $4}'
    emphazer · 2018-10-05 13:01:03 271

  • 1
    curl -s https://ip-ranges.amazonaws.com/ip-ranges.json | awk -F'"' '/ip_prefix/ {print $4}'
    emphazer · 2018-10-05 12:59:33 257

  • 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 12:50:48 266
  • 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 13:12:03 232
  • 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 12:54:06 234
  • 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 12:08:10 242
  • 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 10:28:26 224
  • 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 17:30:47 223

  • 0
    mknod -m 0666 /dev/null c 1 3
    emphazer · 2018-08-16 12:10:16 221
  • 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 11:46:26 238
  • (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 11:23:28 135
  • # 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 17:30:37 124

  • 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 96

  • 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 94
  • 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 94
  • 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 93
  • 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 91
  • 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 90

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Kill all processes that don't belong to root/force logoff
explanation: grep -- displays process ids -v -- negates the matching, displays all but what is specified in the other options -u -- specifies the user to display, or in this case negate The process loops through all PIDs that are found by pgrep, then orders a forced kill to the processes in numerical order, effectively killing the parent processes first including the shells in use which will force the users to logout. Tested on Slackware Linux 12.2 and Slackware-current

Define Google Chrome urpmi media source for Mandriva/Mageia (works for both 32-bit and 64-bit systems)
This command adds a urpmi media source called "google-chrome" to the urpmi configuration on Mandriva or Mageia. Needs to be run as root. We specify the option "--update" so that when Google provides a newer version of Google Chrome web browser in their download system then running a system update (eg: "urpmi --auto-update") will result in our copy of Google Chrome getting updated (along with any other Mandriva/Mageia pending updates). To install Google Chrome from this source, use: urpmi google-chrome-stable #install Google chrome web browser

Install a basic FreeBSD system
Install a basic FreeBSD system on a distant server. I use this to install FreeBSD on servers that can only boot a Linux rescue system. This sytem loads on ram when booted, so it is possible to install freely. You can even install on ZFS root !

Sprunge.us - CLI alternative to PasteBin.com
NAME sprunge: command line pastebin: SYNOPSIS | curl -F 'sprunge=

Find usb device
I often use it to find recently added ou removed device, or using find in /dev, or anything similar. Just run the command, plug the device, and wait to see him and only him

Rename files in batch

Manipulate the metadata and edit the create time (This will change date to 1986:11:05 12:00 - Date: 1986 5th November, Time: 12.00) and then it will set modify date to the same as alldate.

Compare a remote dir with a local dir
You can compare directories on two different remote hosts as well: $ diff -y

Dump dvd from a different machine onto this one.
You can use this to directly dump from machine A (with dvd drive) to machine B (without dvd drive) . I used this to copy dvd using my friend's machine to my netbook. Above command is to be issued on machine B. Advantages : 1) No wasting time dumping first to machine A and then copying to Machine B. 2) You dont need to use space on Machine A. In fact, this will work even when Machine A doesnt have enough hdd space to dump the DVD. Use -C ssh option on slow networks (enables compression). you can replace "dd if=/dev/dvd" with any ripping command as long as it spews the iso to stdout.

shell bash iterate number range with for loop
Bash's arithmetic evaluation.


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