Commands by wejn (9)

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List your sudo rights
List the commands you have the right to use with sudo.

Chrome sucks

Find and delete oldest file of specific types in directory tree
This works on my ubuntu/debian machines. I suspect other distros need some tweaking of sort and cut. I am sure someone could provide a shorter/faster version.

Search for a string inside all files in the current directory
Searches all files,dirs (also hidden) recursively

deaggregate ip ranges
Taking file with ip ranges, each on it's own line like: $cat ipranges.txt 213.87.86.160-213.87.86.193 213.87.87.0-213.87.88.255 91.135.210.0-91.135.210.255 command returns deaggregated ip ranges using ipcalc deaggregate feature like that: 213.87.86.160/27 213.87.86.192/31 213.87.87.0/24 213.87.88.0/24 91.135.210.0/24 Useful for configuring nginx geo module

Sort the current buffer in vi or vim.
vim 7 or higher has internal sort, too 'sort n' for numbers

Take aWebcam Picture When the Mouse Moves
This takes a webcam picture every everytime the mouse is moved (waits 10 seconds between checking for movement) and stores the picture wherever you want it. Ideas: Use in conjunction with a dropbox type application to see who is using your computer Use /dev/input/mice if /dev/input/mouse* doesn't work Use the bones of this to make a simple screensaver

Mount important virtual system directories under chroot'ed directory
The command is useful when, e.g., booting an existing system with a rescue or installation CD where you need to chroot into the hard-disk and be able to do stuff which accesses kernel info (e.g. when installing Ubuntu desktop with LVM2 you need to mount and chroot the hard disk from a shell window in order to install packages and run initramfs inside chroot). The command assumes that /mnt/xxx is where the chroot'ed environment's root file system on the hard disk is mounted.

Display time of accounts connection on a system
Works on CentOS ad OpenBSD too, display time of accounts connection on a system, -p option print individual user's statistics.

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


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