Commands by luishka (3)

  • convert permissions in ls to octal


    -4
    ls -l | sed -e 's/--x/1/g' -e 's/-w-/2/g' -e 's/-wx/3/g' -e 's/r--/4/g' -e 's/r-x/5/g' -e 's/rw-/6/g' -e 's/rwx/7/g' -e 's/---/0/g'
    luishka · 2010-01-31 22:41:02 16
  • ramdomize echo 'hello world!'

    ramdomize the execution of the command echo 'hello world!'


    -8
    (($RANDOM%6)) || echo 'hello world!'
    luishka · 2009-05-27 08:11:08 12
  • Today's date on a yearly calendar...

    Today's date on a yearly calendar... credits to http://lifehacker.com/250825/cli-fun--todays-date-on-a-yearly-calendar Show Sample Output


    0
    cal -y | tr '\n' '|' | sed "s/^/ /;s/$/ /;s/ $(date +%e) / $(date +%e | sed 's/./#/g') /$(date +%m | sed s/^0//)" | tr '|' '\n'
    luishka · 2009-05-26 20:31:26 713

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Show all detected mountable Drives/Partitions/BlockDevices
Yields entries in the form of "/dev/hda1" etc. Use this if you are on a new system and don't know how the storage hardware (ide, sata, scsi, usb - with ever changing descriptors) is connected and which partitions are available. Far better than using "fdisk -l" on guessed device descriptors.

Mount/unmount your truecrypted file containers
This should automatically mount it to /media/truecrypt1. Further mounts will go to /media/truecrypt2, and so on. You shouldn't need sudo/su if your permissions are right. I alias tru='truecrypt' since tr and true are commands. To explicitly create a mount point do: tru volume.tc /media/foo To make sure an GUI explorer window (nautilus, et al) opens on the mounted volume, add: --explorer To see what you currently have mounted do: tru -l To dismount a volume do: tru -d volume.tc. To dismount all mounted volumes at once do: tru -d Tested with Truecrypt v6.3a / Ubuntu 9.10

total text files in current dir

Record camera's output to a avi file
video.avi is the resulting file. Press Ctrl+c to stop the recording. You can change the OVC option to another to record into a different format.

Create incremental snapshots of individual folders using find and tar-gzip
Creates an incremental snapshot of individual folders.

Set laptop display brightness
Run as root. Path may vary depending on laptop model and video card (this was tested on an Acer laptop with ATI HD3200 video). $ cat /proc/acpi/video/VGA/LCD/brightness to discover the possible values for your display.

Test file system performance
You need bonnie++ package for this. More detail than a simple hdparm -t /dev/sda would give you. the -d is the directory where it performs writes/reads for example I use /tmp/scratch with 777 permissions Bonnie++ benchmarks three things: data read and write speed, number of seeks that can be performed per second, and number of file metadata operations that can be performed per second.

Create a video screencast (capture screen) of screen portion, with audio (the audio you hear, not your mic)
Errors in output don't matter. Stop recording: ctrl-c. Result playable with Flash too. IMPORTANT: Find a Pulse Audio device to capture from: pactl list | grep -A2 'Source #' | grep 'Name: ' | cut -d" " -f2

Kill most recently created process.
Kills the most recently created firefox process.

back ssh from firewalled hosts
host B (you) redirects a modem port (62220) to his local ssh. host A is a remote machine (the ones that issues the ssh cmd). once connected port 5497 is in listening mode on host B. host B just do a ssh 127.0.0.1 -p 5497 -l user and reaches the remote host'ssh. This can be used also for vnc and so on.

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