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 9
  • 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 7
  • 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 7
  • 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 7
  • Reuse last parameter

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


    15
    !$
    Neo23x0 · 2010-11-27 14:24:14 9
  • 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 40
  • 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 10
  • 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 7
  • 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 81
  • 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


    101
    !*
    Neo23x0 · 2009-06-21 17:58:01 22

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List your MACs address
The output of ifconfig is localized, using it will fail in non-English environment. "ip" command in iproute2 provides a consistent output and thus is more robust

Find usb device in realtime
Using this command you can track a moment when usb device was attached.

Watch the disk fill up with change highlighting
If you add the -d flag each difference in the command's output will be highlighted. I also monitor individual drives by adding them to df. Makes for a nice thin status line that I can shove to the bottom of the monitor.

Show word-by-word differences between two latex files, in color

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"

Simple Video Surveillance by email
This takes a picture (with the web cam) every 5 minutes, and send the picture to your e-mail. Some systems support mail -a "References: " so that all video surveillance emails are grouped in a single email thread. To keep your inbox clean, it is still possible to filter and move to trash video surveillance emails (and restore these emails only if you really get robbed!) For instance with Gmail, emails sent to me+trash@gmail.com can be filtered with "Matches: DeliveredTo:me+trash@gmail.com"

Insert a line for each n lines
specially usefull for sql scripts with insert / update statements, to add a commit command after n statements executed.

Using tput to save, clear and restore the terminal contents
Very useful for interactive scripts where you would like to return the terminal contents to its original state before the script was run. This would be similar to how vi exits and returns you to your original terminal screen. Save and clear the terminal contents with: $tput smcup Execute some commands, then restore the saved terminal contents with: $tput rmcup

Google dictionary of word definitions
$ wget -qO - "http://www.google.com/dictionary/json?callback=dict_api.callbacks.id100&q=steering+wheel&sl=en&tl=en&restrict=pr,de&client=te" this does the actual google dictionary query, returns a JSON string encapsulated in some fancy tag $ sed 's/dict_api\.callbacks.id100.//' here we remove the tag beginning $ sed 's/,200,null)//' and here the tag end There are also some special characters which could cause problems with some JSON parsers, so if you get some errors, this is probably the case (sed is your friend). I laso like to trim the "webDefinitions" part, because it (sometimes) contains misleading information. $ sed 's/\,\"webDefinitions.*//' (but remember to append a "}" at the end, because the JSON string will be invalid) The output also contains links to mp3 files with pronounciation. As of now, this is only usable in the English language. If you choose other than English, you will only get webDefinitions (which are crap).

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

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