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 34
  • 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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Have a smile
Outputs utf-8 smileys

See system users

Run a script in parrallel over ssh
Runs a local script over ssh assuming ssh keys are in place. -P argument prints results to stdout. # Uses - https://code.google.com/p/parallel-ssh/

Run a command as root, with a delay
$ sleep 1h ; sudo command or $ sudo sleep 1h ; sudo command won't work, because by the time the delay is up, sudo will want your password again.

Remove a line from a file using sed (useful for updating known SSH server keys when they change)
remove the host for the .ssh/know_host file

Amazing real time picture of the sun in your wallpaper
Changes the wallpaper for the last IR picture of the sun taken by SOHO satellite. Lesser size, try $ curl http://sohowww.nascom.nasa.gov/data/realtime/eit_195/512/latest.jpg | xli -onroot -fullscreen -xzoom 120 -yzoom 120 -border black stdin I use inside kalarm(kde), updating every 15 minutes needs xli , curl

Bash: escape '-' character in filename
If you don't escape the - of the filename, you will get the command interpreting it as a parameter, returning (in the best case) an error.

Upgrade pip-installed python packages

make, or run a script, everytime a file in a directory is modified
Uses inotifywait from inotify-tools ( http://wiki.github.com/rvoicilas/inotify-tools/ ), that is compatible only with linux. Usefull when you work with files that have to be compiled.. latex, haml, c..

Obtain last stock quote from google API with xmlstarlet

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