Commands by emphazer (24)

  • 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 2
  • 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 1

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

  • 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 5

  • 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 3

  • 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

  • 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

  • 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
  • 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
  • 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
  • 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 3
  • 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 0
  • 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 0

  • 0
    mknod -m 0666 /dev/null c 1 3
    emphazer · 2018-08-16 12:10:16 1
  • 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 0
  • (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 0
  • # 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 0

  • 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 0

  • 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 0
  • 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 0
  • 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 0
  • 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 0
  • 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 2

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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"

A bit of privacy in .bash_history
Don't track in history commands starting with whitespace. Moreover ignore duplicates from history. To be set in .bashrc ex. $ export HISTCONTROL=ignoreboth $   echo antani $   history|grep -c antani 0

autossh + ssh + screen = super rad perma-sessions
Only useful for really flakey connections (but im stuck with one for now). Though if youre in this situation ive found this to be a good way to run autossh and it does a pretty good job of detecting when the session is down and restarting. Combined with the -t and screen commands this pops you back into your working session lickety split w/ as few headaches as possible. And if autossh is a bit slow at detecting the downed ssh connection, just run this in another tab/terminal window to notify autossh that it should drop it and start over. Basically for when polling is too slow. kill -SIGUSR1 `pgrep autossh`

Avoiding history file to be overwritten
If histappend options is set in bash, the file .bash_history will not be overwrite and history list is append to it.

Process command output line by line in a while loop
This snippet allows to process the output of any bash command line by line.

Find ulimit values of currently running process
When dealing with system resource limits like max number of processes and open files per user, it can be hard to tell exactly what's happening. The /etc/security/limits.conf file defines the ceiling for the values, but not what they currently are, while $ ulimit -a will show you the current values for your shell, and you can set them for new logins in /etc/profile and/or ~/.bashrc with a command like: $ ulimit -S -n 100000 >/dev/null 2>&1 But with the variability in when those files get read (login vs any shell startup, interactive vs non-interactive) it can be difficult to know for sure what values apply to processes that are currently running, like database or app servers. Just find the PID via "ps aux | grep programname", then look at that PID's "limits" file in /proc. Then you'll know for sure what actually applies to that process.

Recursively Find Images, Convert to JPEGS and Delete
Simple command to convert a large number of images into jpeg-format. Will delete originals after conversion.

Puts every word from a file into a new line
Basically it creates a typical word list file from any normal text.

Reboot machine when everything is hanging
If the machine is hanging and the only help would be the power button, this key-combination will help to reboot your machine (more or less) gracefully. R - gives back control of the keyboard S - issues a sync E - sends all processes but init the term singal I - sends all processes but init the kill signal U - mounts all filesystem ro to prevent a fsck at reboot B - reboots the system Save your file before trying this out, this will reboot your machine without warning! http://en.wikipedia.org/wiki/Magic_SysRq_key

Test file system performance
You need bonnie++ package for this. More detail than a simple hdparm -t /dev/sda would give you. the -d is the directory where it performs writes/reads for example I use /tmp/scratch with 777 permissions Bonnie++ benchmarks three things: data read and write speed, number of seeks that can be performed per second, and number of file metadata operations that can be performed per second.


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