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ssh hostchange know_host improver

If you work in an environment, where some ssh hosts change regularly this might be handy...
This is sample output - yours may be different.
-1

sshostnew () {sed -i "$1d" $HOME/.ssh/known_hosts ; }

_john · 2011-11-07 10:33:04 10
Create a false directory structure for testing your commands

You could avoid xargs and sed in this case (shorter command and less forking): At least bash and zsh have some mighty string modifiers. I would also suggest using find with exec option to get more flexibility. You may leave out or include "special" file for example.
This is sample output - yours may be different.
0

for i in /usr/bin/* ;do touch ${i##*/}; done

_john · 2011-10-20 12:38:45 3
Install 4 new package files

after kernel build with make deb-pkg, I like to install the 4 newest packages that exist in the directory. Beware: might be fewer for you....
This is sample output - yours may be different.
0

sudo dpkg -i `ls -tr *.deb | tail -n4`

_john · 2011-10-09 14:20:11 3
Number of CPU's in a system

All Linux Systems I try also have an empty line per cpu in /proc/cpuinfo... little shorter then... Show Sample Output
This is sample output - yours may be different.
```
4
```
0

grep -c '^$' /proc/cpuinfo

_john · 2011-10-09 14:05:14 3
Remove all unused kernels with apt-get

since awk was already there one can use it instead of the 2 greps. might not be faster, but fast enough
This is sample output - yours may be different.
0

apt-get remove $(dpkg -l | awk "/^ii linux-(image|headers)/ && ! /`uname -r`/ {print \$2}")

_john · 2011-10-09 13:58:47 4

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Selecting a random file/folder of a folder

Also looks in subfolders

export iPad App list to txt file

This will generate the same output without changing the current directory, and filepath will be relative to the current directory. Note: it will (still) fail if your iTunes library is in a non-standard location.

Remove Suspend option from XFCE logoff dialog

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"

Insert the last argument of the previous command

for example if you did a: $ ls -la /bin/ls then $ ls !$ is equivalent to doing a $ ls /bin/ls

Rename files in batch

Get your outgoing IP address

Get your external ip adress thanks to http://www.icanhazip.com

Detect illegal access to kernel space, potentially useful for Meltdown detection

Based on capsule8 agent examples, not rigorously tested

Copy with progress

Create a tar file with the current date in the name.

Same, but count of signs is little less :) .

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Commands by _john (5)

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