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Show what PID is listening on port 80 on Linux

Get current stable kernel version string from kernel.org
depends on "jq" This is more reliable in my opinion.

Backup with versioning
Apart from an exact copy of your recent contents, also keep all earlier versions of files and folders that were modified or deleted. Inspired by EVACopy http://evacopy.sourceforge.net

Cleanup Python bytecode files
This command will erase all bytecode versions of Python modules under the current directory.

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

Load another file in vim
You can then switch from a file to another with ^W^W

Graphical tree of sub-directories with files
The command finds every item within the directory and edits the output so that subdirectories are and files are output much like the tree command

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"

Get the ip registered to a domain on OpenWRT
I use this in a script on my openwrt router to check if my DynDNS needs to be updated, saves your account from being banned for blank updates.

Get information on your graphics card on linux (such as graphics memory size)
probably only works if you have one graphics card. used this: http://www.cyberciti.biz/faq/howto-find-linux-vga-video-card-ram/ as reference can be expanded, for example: $ lspci -v -s `lspci | awk '/VGA/{print $1}'` | sed -n '/Memory.*, prefetchable/s/.*\[size=\([^]]\+\)\]/\1/p' will just get the amount of prefetchable memory compare to: $ lshw -C display which does not give the size (it does give byte ranges and you could calculate the size from that, but that's a pain) Also uses a command which is not standard on linux; wheras lspci is a core utility provided by most systems


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