Commands by Alanceil (12)

  • In Python version 3, the module was merged into http.server. Gentlemen, change your aliases. Show Sample Output


    39
    python -m http.server
    Alanceil · 2010-12-17 12:52:45 37
  • The unlock command for KDE 4.3 has changed from krunner_lock, this process doesn't exist anymore. So here's the update :-) If qdbus complains about not being able to find X, put a "DISPLAY=:0 " (:0 being your X server display) in front of the command.


    6
    qdbus org.kde.screenlocker /MainApplication quit
    Alanceil · 2009-08-27 13:57:00 3
  • On a Gentoo system, this command will tell you which packets you have installed and sort them by how much space they consume. Good for finding out space-hogs when tidying up disk space. Show Sample Output


    1
    equery s | sed 's/(\|)/ /g' | sort -n -k 9 | gawk '{print $1" "$9/1048576"m"}'
    Alanceil · 2009-07-30 01:12:10 5
  • Intended for dynamic ip OpenDNS users, this command will update your OpenDNS network IP. For getting your IP, you can use one of the many one-liners here on commandlinefu. Example: I use this in a script which is run by kppp after it has successfully connected to my ISP: --- #!/bin/bash IP="`curl -s http://checkip.dyndns.org/ | grep -o '[[:digit:].]\+'`" PW="hex-obfuscated-pw-here" if [ "$IP" == "" ] ; then echo 'Not online.' ; exit 1 else wget -q --user=topsecret --password="`echo $PW | xxd -ps -r`" 'https://updates.opendns.com/nic/update?hostname=myhostname&myip='"$IP" -O - /etc/init.d/ntp-client restart & fi --- PS: DynDNS should use a similar method, if you know the URL, please post a comment. (Something with members.dyndns.org, if I recall correctly) Show Sample Output


    5
    wget -q --user=<username> --password=<password> 'https://updates.opendns.com/nic/update?hostname=your_opendns_hostname&myip=your_ip' -O -
    Alanceil · 2009-06-22 18:08:42 10
  • Since bash 4.0, you can use ** to recursively expand to all files in the current directory. This behaviour is disabled by default, this command enables it (you'd best put it in your .profile). See the sample output for clarification. In my opinion this is much better than creating hacks with find and xargs when you want to pass files to an application. Show Sample Output


    11
    shopt -s globstar
    Alanceil · 2009-05-05 16:02:44 3
  • This is a (last resort) way to automate applications that provide no other ways for automation, it would send 'Hello world' to the currently active window. See the manpage (and the -text and -window entries) for how to send special characters and target specific windows. An example: Using xwininfo, I get the id of my XPlanet background window: alanceil@kvirasim:19:51:0:~> xwininfo xwininfo: Please select the window about which you would like information by clicking the mouse in that window. xwininfo: Window id: 0x3600001 "Xplanet 1.2.0" Absolute upper-left X: 0 (..etc..) Now I use xvkbd to tell it to close itself: xvkbd -xsendevent -window 0x3600001 -text "Q" Obviously, the best way is to put these commands in a shellscript - just make sure to include a short sleep (sleep .1 should suffice) after each xvkbd call, or some programs will become confused.


    15
    xvkbd -xsendevent -text "Hello world"
    Alanceil · 2009-03-20 18:58:05 9
  • I had a hard time in finding the correct settings to get reasonable output from a coin selector which sends its data over a serial line. In the end, minicom came to the rescue and pointed me on the right track. So, if you need to do something similar, these settings may help you. Replace ttyUSB0 with your device file, 9600 with your baud rate, 5 with your read timeout (10ths of a second), and 1 with the minimum numbers of characters you want to read. You can then open the device file like you are used to do, example: DATA="`xxd -ps -l 5 \"$DEV\"`"


    1
    stty -F "/dev/ttyUSB0" 9600 ignbrk -brkint -icrnl -imaxbel -opost -onlcr -isig -icanon -iexten -echo -echoe -echok -echoctl -echoke time 5 min 1 line 0
    Alanceil · 2009-03-20 14:48:32 6
  • This command will tell lynx to read keystrokes from the specified file - which can be used in a cronjob to auto-login on websites that give you points for logging in once a day *cough cough* (which is why I used -accept_all_cookies). For creating your keystroke file, use: lynx -cmd_log yourfile


    26
    lynx -accept_all_cookies -cmd_script=/your/keystroke-file
    Alanceil · 2009-03-17 00:38:36 6
  • Suppose you made a backup of your hard disk with dd: dd if=/dev/sda of=/mnt/disk/backup.img This command enables you to mount a partition from inside this image, so you can access your files directly. Substitute PARTITION=1 with the number of the partition you want to mount (returned from sfdisk -d yourfile.img). Show Sample Output


    8
    INFILE=/path/to/your/backup.img; MOUNTPT=/mnt/foo; PARTITION=1; mount "$INFILE" "$MOUNTPT" -o loop,offset=$[ `/sbin/sfdisk -d "$INFILE" | grep "start=" | head -n $PARTITION | tail -n1 | sed 's/.*start=[ ]*//' | sed 's/,.*//'` * 512 ]
    Alanceil · 2009-03-06 21:29:13 6
  • wrestool can be found in icoutils (http://www.nongnu.org/icoutils) Show Sample Output


    1
    wrestool -x --output . -t14 /path/to/your-file.exe
    Alanceil · 2009-02-28 22:51:32 5
  • This is useful if you have a program which doesn't work well with multicore CPUs. With taskset you can set its CPU affinity to run on only one core.


    20
    taskset -c 0 your_command
    Alanceil · 2009-02-28 22:38:02 10
  • I use this command to save RTSP video streams over night from one of our national TV stations, so I won't have to squeeze the data through my slow internet connection when I want to watch it the next day. For ease of use, you might want to put this in a file: #!/bin/bash FILE="`basename \"$1\"`" mplayer -dumpstream -dumpfile "$FILE" -playlist "$1"


    9
    mplayer -dumpstream -dumpfile "yourfile" -playlist "URL"
    Alanceil · 2009-02-28 22:18:17 3

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Detect illegal access to kernel space, potentially useful for Meltdown detection
Based on capsule8 agent examples, not rigorously tested

find unreadable file

Write comments to your history.
A null operation with the name 'comment', allowing comments to be written to HISTFILE. Prepending '#' to a command will *not* write the command to the history file, although it will be available for the current session, thus '#' is not useful for keeping track of comments past the current session.

list files recursively by size

check open ports without netstat or lsof

Diff two directories by finding and comparing the md5 checksums of their contents.
Compute the md5 checksums for the contents of two mirrored directories, then sort and diff the results. If everything matches, nothing is returned. Otherwise, any checksums which do not match, or which exist in one tree but not the other, are returned. As you might imagine, the output is useful only if no errors are found, because only the checksums, not filenames, are returned. I hope to address this, or that someone else will!

Create a single-use TCP proxy with copy to stdout
USAGE: gate listening_port host port Creates listening socket and connects to remote device at host:port. It uses pipes for connection between two sockets. Traffic which goes through pipes is wrote to stdout. I use it for debug network scripts.

List alive hosts in specific subnet
Works on any machine with nmap installed. Previous version does not work on machines without "seq". Also works on subnets of any size.

Compose 2 images to 1
Compose 2 images (foreground.jpg with background.jpg) into 1 (image.jpg), the numeric parameters stablish the size of the foreground.jpg image (96x96) and the position x,y (+250+70) relative to the background.jpg image. Images can be any format, jpg, png, bmp, etc...

Set RGB gamma of secondary monitor
This command first determines whether a second screen is connected. If this is the case, it sets the screen's RGB gamma via xrandr. Useful for cheap or slightly defective monitors with a tint. In this example a yellowing/champagne color deviation is compensated for by decreasing the red and the green portion of the image.


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