Commands by Blacksimon

Commands by Blacksimon (3)

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Know status of Caps, Num and Scroll Lock on Netbook w/o Leds

The command lets you know the status of the Caps, Num and Scroll Lock in the terminal. This is useful when the Netbook has no LED indicators Show Sample Output
This is sample output - yours may be different.
```
black @ blacksimon ? ~ $ xset -q | grep -e Caps
    00: Caps Lock:   off    01: Num Lock:    off    02: Scroll Lock: off
```
0

xset -q | grep -e Caps

Blacksimon · 2015-03-14 18:40:51 8
Prevent aggressive Hdd spindown in Laptop battery powered

With many distro if a laptop will be running on batteries, the settings of the power management utility try to optimize the performance and behavior to increase battery life. Very often happens that the default settings are too aggressive and cause continuous Hdd spindown with the risk of damage. This command turns hdd power management off.
This is sample output - yours may be different.
0

sudo hdparm -B255 -S0 /dev/sda

Blacksimon · 2015-03-13 21:29:10 10
Restrict the use of dmesg for current user/session

Linux offers an interesting option to restrict the use of dmesg. It is available via /proc/sys/kernel/dmesg_restrict. You can check the status with: cat /proc/sys/kernel/dmesg_restrict Alternatively you can use sysctl: sudo sysctl -w kernel.dmesg_restrict=1 To make your change persistent across reboot, edit a fille in /etc/sysctl.d/.
This is sample output - yours may be different.
1

sudo sh -c 'echo 1 > /proc/sys/kernel/dmesg_restrict'

Blacksimon · 2015-03-13 20:54:45 11

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Which Twitter user are you?

This will tell you which twitter user you are chronologically. For example, a number of 500 means you were the 500th user to create a twitter account.

Convert IP octets to HEX with no dots.

Converts IP octets to hex using printf command. Useful for generating pxeboot aliases in the pxelinux.cfg folder.

Perl Command Line Interpreter

Can also just use the debug mode like this.

get all Google ipv4 subnets for a iptables firewall for example

multiline data block parse and CSV data extraction with perl

extract data in multiline blocks of data with perl pattern matching loop

Convert text to uppercase

Usage: upper [STRING]...

execute a shell with netcat without -e

Shorter version with proper stderr redirection .

Search some text from all files inside a directory

Easily decode unix-time (funtion)

More recent versions of the date command finally have the ability to decode the unix epoch time into a human readable date. This function makes it simple to utilize this feature quickly.

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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