Commands by sil (8)

  • Random numbers with Ruby

    There's been a few times I've needed to create random numbers. Although I've done so in PERL, I've found Ruby is actually faster. This script generates 20 random "10" digit number NOT A RANDOM NUMBER. Replace 20 (1..20) with the amount of random numbers you need generated Show Sample Output


    3
    ruby -e "puts (1..20).map {rand(10 ** 10).to_s.rjust(10,'0')}"
    sil · 2009-05-27 19:52:53 8
  • Inserting a decimal every third digit

    self explanatory see sample output Show Sample Output


    -2
    perl -lpe'1 while s/^([-+]?\d+)(\d{3})/$1.$2/'
    sil · 2009-02-18 21:54:22 7
  • Glutton for punishment

    Alrighty, so I was really bored ;) Show Sample Output


    -5
    ''=~('(?{'.('_/@.*@'^'/])@^`').'"'.('"/_/@]/--!.:@</:[@(:/:^'^'[@*]`>@@@@@^`[@_(`@_]_|').',$/})')
    sil · 2009-02-18 17:22:26 14
  • Comma insertions

    Insert a comma where necessary when counting large numbers. I needed to separate huge amounts of packets and after 12+ hours of looking in a terminal, I wanted it in readable form. Show Sample Output


    2
    perl -pe '$_=reverse;s/\d{3}(?=\d)(?!.*?\.)/$&,/g;$_=reverse'
    sil · 2009-02-18 16:34:18 16
  • Block known dirty hosts from reaching your machine

    Blacklisted is a compiled list of all known dirty hosts (botnets, spammers, bruteforcers, etc.) which is updated on an hourly basis. This command will get the list and create the rules for you, if you want them automatically blocked, append |sh to the end of the command line. It's a more practical solution to block all and allow in specifics however, there are many who don't or can't do this which is where this script will come in handy. For those using ipfw, a quick fix would be {print "add deny ip from "$1" to any}. Posted in the sample output are the top two entries. Be advised the blacklisted file itself filters out RFC1918 addresses (10.x.x.x, 172.16-31.x.x, 192.168.x.x) however, it is advisable you check/parse the list before you implement the rules Show Sample Output


    33
    wget -qO - http://infiltrated.net/blacklisted|awk '!/#|[a-z]/&&/./{print "iptables -A INPUT -s "$1" -j DROP"}'
    sil · 2009-02-18 16:08:23 33
  • Forget fortunes in your terminal this grabs a random

    I've got this posted in one of my .bash_profiles for humor whenever I log in. Show Sample Output


    -2
    wget -qO - snubster.com|sed -n '65p'|awk 'gsub(/<span><br>.*/,"")&&1'|perl -p -e 's:myScroller1.addItem\("<span class=atHeaderOrange>::g;s:</span> <span class=snubFontSmall>::g;s:&quot;:":g;s:^:\n:g;s:$:\n:'
    sil · 2009-02-18 15:05:13 9
  • Insert a colon between every two digits

    I sometimes have large files of MAC addresses stored in a file, some databases need the information stored with the semicolon (makes for easier programming a device) others don't. I have a barcode to text file scanner which usually butchers MAC addresses so this was the fix> I initially did this in awk ;) awk '{for(i=10;i>=2;i-=2)$0=substr($0,1,i)":"substr($0,i+1);print}' mac_address_list Show Sample Output


    6
    sed 's/\(..\)/\1:/g;s/:$//' mac_address_list
    sil · 2009-02-18 14:38:37 7
  • Check ps output to see if file is running, if not start it

    This comes in handy if you have daemons/programs that have potential issues and stop/disappear, etc., can be run in cron to ensure that a program remains up no matter what. Be advised though, if a program did core out, you'd likely want to know why (gdb) so use with caution on production machines.


    3
    ps -C thisdaemon || { thisdaemon & }
    sil · 2009-02-18 14:12:17 6

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High resolution video screen recording
$ gorecord foo.mp4 I've tried all of the screen recorders available for Linux and this is easily the best. xvidcap segfaults; VNC is too much hassle. There are alternatives of this command already here that I am just too lazy to reply to. Messing with the frames per second option, -r, 25 seems to be the best. Any lower and the video will look like a flipbook, if it records at all - -r 10 won't - any faster is the same, oddly enough. Edit: CLF doesn't like my long command to add audio, so here it is in the description. $ goaddaudio() ${ $if [ $# != 3 ]; then $ echo 'goaddaudio < audio > < src video > < dst video >' $ return $ fi $ $ f=goaddaudio$RANDOM $ ffmpeg -i "$2" &> $f $ d=$( grep Duration $f | awk '{print $2}' | tr -d ',' ) && $ rm $f && $ ffmpeg -i "$1" -i "$2" -r 25 -ab 192k -ar 44100 -sameq -t $d "$3" $}

Download an Entire website with wget

Convert a bunch of HTML files from ISO-8859-1 to UTF-8 file encoding in a folder and all sub-folders
This is my first attempt at converting all HTML files to UTF-8 file encoding, including all subfolders. Theres probably a much more compact way to do it, but I'm quite proud of it with my windows background ;)

Grab all .flv files from a webpage to the current working directory
I wanted all the 'hidden' .flv files from the http link in the command line; wget seemed appropriate, fed with output from lynx, grep the flv files and the normalised via sed (to remove the numeric bullet). Similar to the 'Grab mp3 files' fu. Replace link with your own, grep arg with something more interesting ;) See here for something along the same lines... http://www.commandlinefu.com/commands/view/1006/grab-mp3-files-from-your-favorite-netcasts-mp3blog-or-sites-that-often-have-good-mp3s Hope you find it useful! Improvements welcome, naturally.

return external ip

Find the top 10 directories containing the highest number of files
It can be used to pinpoint the path(s) where the largest number of files resides when running out of free i-nodes

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"

recursively change file name from uppercase to lowercase (or viceversa)
Example of zsh globing, glob qualifier, and substitution: -Q state that the parameter will contain a glob qualifier. (**/)(*) is recursive (.) is our glob qualifier, with states the match is a file "." The first parameter $1, is then substituted with $2 but with lowercasing '(L)' ... a (U) would of course be from lower to upper.

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

Synchronize both your system clock and hardware clock and calculate/adjust time drift
Do not run this command if you already have ntpd running! This needs to run as root, for example with sudo: $ sudo ntpdate pool.ntp.org && sudo hwclock --systohc && sudo hwclock --adjust This command will fetch accurate time from NTP servers and synchronize your system clock, then it will use the system clock to synchronize your hardware clock, and will calculate the time drift.

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