Commands using head (314)

  • Get the user with the top number of logins

    Get an approximation of who the workstation is assigned to. You can wrap it in su - "$()" if you want to log into a shell as that user. Show Sample Output


    0
    last | grep -i console | grep -iv 'root' | cut -f 1 -d ' ' | sort | uniq -c | sort -nr | awk '{print $2}' | head -1
    phyxia · 2015-07-20 18:07:40 10
  • Generate a random string (for password, hash or whatever)

    Useful when you need to generate password or random hash string. If you need longer string adjust parameter for "head -c 20" Show Sample Output


    0
    dd if=/dev/urandom bs=1k count=1 2>/dev/null|LC_CTYPE=C tr -dc 'abcdefghijklmnopqrstuvwxyz0123456789!@#%^&*(-_=+)'|head -c 20
    nitrogear · 2015-07-25 21:24:28 9
  • ps to show child thread PIDs


    0
    ls -1 /proc/$(ps ax | grep <Process Name> | head -n 1 | awk '{print $1;}')/task | tail -n +2
    happymarmoset · 2015-10-06 07:44:48 10
  • Shows which commands you use the most.


    0
    cut -f1 -d" " ~/.bash_history | sort | uniq -c | sort -nr | head -n 30
    kenorb · 2015-10-09 16:11:37 10
  • Extract the URL of the first mp3 out of a podcast xml feed and add it it to current mpd playlist

    Quick way to get the URL of the most recent audio file out of a podcast xml feed without any fancy xml parsing tools. Just curl, grep and head


    0
    mpc add `curl -s http://link.to/podcast/feed.xml | grep -o 'https*://[^"]*mp3' | head -1`
    tbon3r · 2015-10-11 09:17:35 9
  • yet another random password generator.

    this one includes special characters. note some some chars may be disallowed on windows systems. *nix will allow pretty much any character in a password except a carriage return. you do not want non printing characters in your password, so this is limited to the printable chars displayed on a keyboard , less space and return. edited to fix minor typo Show Sample Output


    0
    tr -dc '[:print:]' < /dev/urandom | fold -w10 |head -n1 |sed 's/ //g'
    wr250 · 2016-01-09 13:43:16 12
  • Returns the N most recently modified files from anywhere 'below' (and including) the current working directory, in order, with details.

    Returns a list, with attributes (think `ls -l`), in reverse chronological order. N is a single numeric parameter. Robust against unfriendly filenames and directory structures. Show Sample Output


    0
    nmf() { find . -type f -printf '%T@ ' -print0 -printf '\n' | sort -rn | head -"$1" | cut -f2- -d" " | tr -d "\0" | tr "\n" "\0" | xargs -0 ls -Ulh; }
    incidentnormal · 2016-03-04 14:53:14 12
  • Display the top ten running processes - sorted by memory usage

    Display the top processes sorted by memory usage. This is mostly useful because it's easy to remember and can give me a quick 'top' view of a group of servers when used over pssh. (Though I'd recommend |head -10 to minimize the output). Show Sample Output


    0
    top -b -o +%MEM |head -17
    dak1n1 · 2016-03-16 22:14:34 12
  • Convert json files to tsv text blob

    Grabs the first JSON file in the directory, reads its keys, prints TSV, then prints all the json files' values as TSV. Nested objects appear as json. Unhappy times if your json has literal tabs in it. Show Sample Output


    0
    jq -r 'keys | join("\t")' $(ls -f *.json | head -1) && jq -Sr 'to_entries | [ .[] | .value | tostring ] | join("\t")' *.json
    drjeats · 2016-04-08 23:30:30 12
  • List latest 5 modified files recursively

    This command will find any named file types in / between two dates then will list all the metadata of those files in long format and human readable form. Adding a 't' flag to the ls command sorts the files by modified time. After all that the head -5 lists the first 5 which can be changed.


    0
    ls -laht `find / -name "*.*" -type f -newermt "2016-04-05" ! -newermt "2016-04-10"`|head -5
    ubercoo · 2016-04-19 14:26:23 10
  • Finding commands to create alias for

    by determining most popular use in history using percentage . Show Sample Output


    0
    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
    turrtle13 · 2016-04-24 17:21:35 9
  • Password server

    This server can be access by a browser or other remote terminal with ncat. I have to use de test && break to allow ctrl-c to close. Show Sample Output


    0
    while [ 1 ]; do cat /dev/urandom | tr -dc ' -~' | head -c 10 | ncat -l 8080 &> /dev/null; test $? -gt 128 && break; done
    xxjcaxx · 2016-05-04 14:36:47 10
  • sorta apache logs by ip frequency


    0
    cat access.log | awk '{print $1}' | sort -n | uniq -c | sort -nr | head -20
    prees · 2016-05-05 20:52:03 13
  • This command watches the top 10 processes currently taking up the most memory with thread & other info, incase you don't want to use the TOP or HTOP command.

    This is a alternate command I like to use instead of TOP or HTOP to see what are the processes which are taking up the most memory on a system. It shows the username, process ID, CPU usage, Memory usage, thread ID, Number of threads associated with parent process, Resident Set Size, Virtual Memory Size, start time of the process, and command arguments. Then it's sorted by memory and showing the top 10 with head. This of course can be changed to suit you needs. I have a small system which is why Firefox is taking so much resources. Show Sample Output


    0
    watch -n .8 'ps -eaLo uname,pid,pcpu,pmem,lwp,nlwp,rss,vsz,start_time,args --sort -pmem| head -10'
    ubercoo · 2016-05-11 01:05:53 11
  • Find top 10 largest files in /var directory (including subdirectories)


    0
    find /var -type f -exec du -h {} \; | sort -rh | head -10
    jiananmail · 2016-05-31 00:21:32 10
  • who is the console user?

    Finds the login id of the user that owns the console. I use it to reset my touchpad after resume from suspend in /etc/pm/sleep.d/s99local


    0
    who | grep :0 | head -1 | cut -d " " -f 1
    mikef5410 · 2016-06-22 17:33:38 12
  • Find 20 most frequently-used shell commands from (bash history)


    0
    tr "\|\;" "\n" < ~/.bash_history | sed -e "s/^ //g" | cut -d " " -f 1 | sort | uniq -c | sort -rn | head -20
    turrtle13 · 2016-07-01 19:27:12 10
  • Display the top ten running processes sorted by the memory usage:


    0
    ps aux | awk '{if ($5 != 0 ) print $2,$5,$6,$11}' | sort -k2rn | head -10 | column -t
    turrtle13 · 2016-07-01 19:40:56 12
  • sort of automaticly install gems that are depend

    When bundle install sucks ...This runs isuckat_ruby.rb and when stderror matches find gem ' it will gem install what ever is missing ... Show Sample Output


    0
    gem install `ruby ./isuckat_ruby.rb 2>&1 | sed -e 's/.*find gem .//g' -e 's/ .*//g' | head -n 1`
    operat0r · 2016-08-03 19:41:27 13
  • Last shutdown date and time of a system


    0
    last -x | grep shutdown | head -1
    creepyjones · 2016-08-10 21:51:48 12
  • simulate Simultaneous connections with curl

    to simulating connections Simultaneous to specific server adress to test penetrations Show Sample Output


    0
    for i in {0..60}; do (curl -Is http://46.101.214.181:10101 | head -n1 &) 2>/dev/null; sleep 1; done;
    aysadk · 2017-01-15 14:32:02 16
  • stress test curl 60 connection simulate


    0
    for i in {0..60}; do (curl -Is http://<domain/ip> | head -n1 &) 2>/dev/null; sleep 1; done;
    aysadk · 2017-01-24 02:47:13 13
  • Find the top most 5 duplicate files in a folder

    To allow recursivity : find -type f -exec md5sum '{}' ';' | sort | uniq -c -w 33 | sort -gr | head -n 5 | cut -c1-7,41- Display only filenames : find -maxdepth 1 -type f -exec md5sum '{}' ';' | sort | uniq -c -w 33 | sort -gr | head -n 5 | cut -c43- Show Sample Output


    0
    find -maxdepth 1 -type f -exec md5sum '{}' ';' | sort | uniq -c -w 33 | sort -gr | head -n 5 | cut -c1-7,41-
    MaDCOw · 2017-02-09 11:36:31 18
  • Print nicely in columns a chunk of text that is separated by tab


    0
    head filename.txt | column -t -s $'\t'
    NLKNguyen · 2017-02-10 23:26:10 20
  • Execute the last line of output from the previous command

    alex@alex-box:~$ sl The program 'sl' is currently not installed. You can install it by typing: sudo apt-get install sl alex@alex-box:~$ dolast Reading package lists... Done Building dependency tree Reading state information... Done The following NEW packages will be installed: sl 0 upgraded, 1 newly installed, 0 to remove and 0 not upgraded.


    0
    alias dolast='$( $(history 2| head -n 1| sed "s/.* //") 2>&1 | tail -n 1)'
    aheinous · 2017-02-25 01:26:49 19
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Terminal - Show directories in the PATH, one per line with sed and bash3.X `here string'

Netcat ftp brute force

Quickly get summary of sizes for files and folders
Use this as a quick and simple alternative to the slightly verbose "du -s --max-depth=1"

Get AWS temporary credentials ready to export based on a MFA virtual appliance
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

List your installed Chromium extensions (with url to each page)
Gives you a list for all installed chrome (chromium) extensions with URL to the page of the extension. With this you can easy add a new Bookmark folder called "extensions" add every URL to that folder, so it will be synced and you can access the names from every computer you are logged in. ------------------------------------------------------------------------------------------------------------------ Only tested with chromium, for chrome you maybe have to change the find $PATH.

Batch rename extension of all files in a folder, in the example from .txt to .md

Create a nifty overview of the hardware in your computer
After the command is done, open the html file in a browser

Source zshrc/bashrc in all open terminals
Put this in your zshrc, source it, then run 'pkill -usr1 zsh' to source it in all open terminals. Also works with bash. More info: http://www.reddit.com/r/commandline/comments/12g76v/how_to_automatically_source_zshrc_in_all_open/

Comparison between the execution output of the last and penultimate command
Useful for checking if there are differences between last and penultimate command.

Send multiple attachments using mailx
If you're users have ever asked your script to email their reports in separate attachments instead of tar'ring them into one file, then you can use this. You'll need the mailx package of course. In Unix you'd want to add an additional parameter "-m" (uuencode foo.txt foo.txt; uuencode /etc/passwd passwd.txt)|mailx -m -s "Hooosa!" someone@cmdfu.com

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