Commands by Neo23x0 (12)

  • Rekursive Grep on Solaris or AIX Systems without GNU egrep -r funcionality


    0
    find . -type f -exec awk '/linux/ { printf "%s %s: %s\n",FILENAME,NR,$0; }' {} \;
    Neo23x0 · 2011-11-29 12:32:06 8
  • Find Malware in the current and sub directories by MD5 hashes

    Command makes use of the Malware Hash Registry (http://www.team-cymru.org/Services/MHR/). It parses the current directory and subdirectories and calculates the md5 hash of the files, then prints the name and sends the hash to the MHR for a lookup in their database. The 3rd value in the result is the detection percentage across a mix of AV packages. Show Sample Output


    11
    IFS=$'\n' && for f in `find . -type f -exec md5sum "{}" \;`; do echo $f | sed -r 's/^[^ ]+/Checking:/'; echo $f | cut -f1 -d' ' | netcat hash.cymru.com 43 ; done
    Neo23x0 · 2011-10-15 03:38:47 5
  • egrep -r replacement for UNIX systems

    Finds a string in files recursively below the current directory on systems without the "egrep" and its "-r" functionality. Show Sample Output


    -5
    find . -type f | xargs grep -l "string"
    Neo23x0 · 2011-08-30 13:22:42 6
  • File rotation without rename command

    Rotates log files with "gz"-extension in a directory for 7 days and enumerates the number in file name. i.e.: logfile.1.gz > logfile.2.gz I needed this line due to the limitations on AIX Unix systems which do not ship with the rename command. Show Sample Output


    1
    for i in {6..1} ; do for f in *.$i.gz ; do mv "$f" "${f/.$i.gz}".$((i+1)).gz 2> /dev/null ; done; done
    Neo23x0 · 2011-04-18 11:44:36 4
  • Reuse last parameter

    Reuse the last parameter of the previous command line Show Sample Output


    15
    !$
    Neo23x0 · 2010-11-27 14:24:14 8
  • Save the Top 2500 commands from commandlinefu to a single text file


    9
    curl http://www.commandlinefu.com/commands/browse/sort-by-votes/plaintext/[0-2500:25] | grep -v _curl_ > comfu.txt
    Neo23x0 · 2010-04-01 08:46:20 37
  • Perl Simple Webserver

    First we accept a socket and fork the server. Then we overload the new socket as a code ref. This code ref takes one argument, another code ref, which is used as a callback. The callback is called once for every line read on the socket. The line is put into $_ and the socket itself is passed in to the callback. Our callback is scanning the line in $_ for an HTTP GET request. If one is found it parses the file name into $1. Then we use $1 to create an new IO::All file object... with a twist. If the file is executable("-x"), then we create a piped command as our IO::All object. This somewhat approximates CGI support. Whatever the resulting object is, we direct the contents back at our socket which is in $_[0].


    5
    perl -MIO::All -e 'io(":8080")->fork->accept->(sub { $_[0] < io(-x $1 ? "./$1 |" : $1) if /^GET \/(.*) / })'
    Neo23x0 · 2010-03-31 15:03:55 8
  • Search Google from the command line

    Adjust Google domain and window width


    6
    curl -A Mozilla http://www.google.com/search?q=test |html2text -width 80
    Neo23x0 · 2009-07-16 22:41:55 10
  • Watch several log files in a single window

    It works like a "tail -f" on several files. Use the number keys 0-9 to set a baseline in the numbered window. Pressing "b" let you scroll back in one of the windows.


    4
    multitail /var/log/messages /var/log/apache2/access.log /var/log/mail.info
    Neo23x0 · 2009-06-22 06:51:11 10
  • Log the current memory statistics frequently to syslog

    Uses logger in a while loop to log memory statistics frequently into the local syslog server.


    3
    while true; do { $(which logger) -p local4.notice `free -m | grep Mem`; sleep 60; } done &
    Neo23x0 · 2009-06-22 00:29:53 6
  • Create a system overview dashboard on F12 key

    Command binds a set of commands to the F12 key. Feel free to alter the dashboard according to your own needs. How to find the key codes? Type read Then press the desired key (example: F5) ^[[15~ Try bind '"\e[15~"':"\"ssh su@ip-address\C-m""" or bind '"\e[16~"':"\"apachectl -k restart\C-m""" Show Sample Output


    18
    bind '"\e[24~"':"\"ps -elF;df -h;free -mt;netstat -lnpt;who -a\C-m"""
    Neo23x0 · 2009-06-21 23:57:20 80
  • Reuse all parameter of the previous command line

    !* is all of the arguments to the previous command rather than just the last one. This is useful in many situations. Here's a simple example: vi cd /stuff oops! [exit vi, twice] !* expands to: cd /stuff


    99
    !*
    Neo23x0 · 2009-06-21 17:58:01 18

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Print a random 8 digit number
Don't need to pipe the output into rs if you just tell jot to use a null separator character.

bulk rename files with sed, one-liner
Far from my favorite, but works in sh and with an old sed that doesn't support '-E'

Delete all but the latest 5 files
yes 6 (tail from 6th line)

List upcoming events on google calendar
Requires googlecl (http://code.google.com/p/googlecl/) Even better when you wrap this in a script and allow the --date=STRING to be $1. Then you can type: whatson "next Thursday" The date string for UNIX date is very flexible. You can also add --cal "[regex]" to the end for multiple calendars.

create screencast (record text and audio simultaneously) using 'script' and 'arecord'
This shell function takes a single argument, which is used as the base name of the .wav, .timing and .session files created. To create a screencast: $ screencast test type and talk ... then type 'exit' or to exit the screencast. test.wav will contain the audio from your screencast. test.session will contain text and control characters needed to paint the screen test.timing will contain timing information needed to synch individual keystrokes in test.session with the audio. to play back: $ aplay test.wav & scriptreplay test.{timing,session} NOTE: because the shell function uses the variable "$!", and bash likes to expand '!' during history expansion, you will need to turn off bash's history before you enter the shell function. This can be achieved using the command $set +H

Extracting frames from a video as jpeg files
This command extracts 10 seconds worth of frames, starting from 00:15:45 position, from filename.avi and stores them into out_frames folder as jpeg files. Subtitles are turned off with -sid 999 option.

Adjust gamma so monitor doesn't mess up your body's clock
[UPDATE: Now works for multiple connected outputs] I woke up around midnight with an urge to do some late night hacking, but I didn't want a bright monitor screwing up my body's circadian rhythm. I've heard that at night blue (short wavelength) lights are particularly bad for your diurnal clock. That may be a bunch of hooey, but it is true that redder (longer wavelength) colors are easier on my eyes at night. This command makes the screen dimmer and adjusts the gamma curves to improve contrast, particularly darkening blues and greens (Rɣ=2, Gɣ=3, Bɣ=4). To reset your screen to normal, you can run this command: $ xrandr | sed -n 's/ connected.*//p' | xargs -n1 -tri xrandr --output {} --brightness 1 --gamma 1:1:1 or, more briefly, $ xgamma -g 1 Note: The sed part is fragile and wrong. I'm doing it this way because of a misfeature in xrandr(1), which requires an output be specified but has no programmatic way of querying available outputs. Someone needs to patch up xrandr to be shell script friendly or at least add virtual outputs named "PRIMARY" and "ALL". . Todo: Screen should dim (gradually) at sunset and brighten at sunrise. I think this could be done with a self-resubmitting at job, but I'm running into the commandlinefu 127 character limit just getting the sunrise time: $ wget http://aa.usno.navy.mil/cgi-bin/aa_pap.pl --post-data=$(date "+xxy=%Y&xxm=%m&xxd=%d")"&st=WA&place=Seattle" -q -O- | sed -rn 's/\W*Sunrise\W*(.*)/\1/p' I hope some clever hacker comes up with a command line interface to Google's "OneBox", since the correct time shows up as the first hit when googling for "sunrise:cityname". . [Thank you to @flatcap for the sed improvement, which is much better than the head|tail|cut silliness I had before. And thank you to @braunmagrin for pointing out that the "connected" output may not be on the second line.]

copy partition table from /dev/sda to /dev/sdb

List only hidden files
You can omit the -d to see what's inside directories. In that case, you may want -a to see dotfiles inside those directories. (Otherwise you don't need -a since you're explicitly looking at them.)

SMTP Analysis
This works just as well for SMTP. You could run this on your mail server to watch e-mail senders and recipients: tcpdump -l -s0 -w - tcp dst port 25 | strings | grep -i 'MAIL FROM\|RCPT TO'

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