Commands by Alanceil (12)

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


    32
    python -m http.server
    Alanceil · 2010-12-17 12:52:45 0
  • 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 0
  • 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


    0
    equery s | sed 's/(\|)/ /g' | sort -n -k 9 | gawk '{print $1" "$9/1048576"m"}'
    Alanceil · 2009-07-30 01:12:10 0
  • Intended for dynamic ip OpenDNS users, this command will update your OpenDNS network IP. For getting your IP, you can use one of the many one-liners here on commandlinefu. Example: I use this in a script which is run by kppp after it has successfully connected to my ISP: --- #!/bin/bash IP="`curl -s http://checkip.dyndns.org/ | grep -o '[[:digit:].]\+'`" PW="hex-obfuscated-pw-here" if [ "$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 4
  • 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 1
  • 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 1
  • 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 0
  • 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 0
  • 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


    6
    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 3
  • 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 0
  • 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 1
  • 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 0

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Mount a partition from within a complete disk dump
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).

Silently Execute a Shell Script that runs in the background and won't die on HUP/logout
This command runs your shell script in the background with no output of any kind, and it will remain running even after you logout.

Use file(1) to view device information
file(1) can print details about certain devices in the /dev/ directory (block devices in this example). This helped me to know at a glance the location and revision of my bootloader, UUIDs, filesystem status, which partitions were primaries / logicals, etc.. without running several commands. See also: $ file -s /dev/dm-* $ file -s /dev/cciss/* etc..

Find all active ip's in a subnet

Resume scp of a big file

xargs for builtin bash commands
Similar to xargs -i, but works with builtin bash commands (rather than running "bash -c ..." through xargs)

Create an SSH tunnel for accessing your remote MySQL database with a local port

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

Go (cd) directly into a new temp folder
This command create a new temp directory using mktemp (to avoid collisions) and change the current working directory to the created directory.

check site ssl certificate dates
remotely connects to an https site, fetches the ssl certificate and displays the valid dates for the cert


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