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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

kill some pids without specific pid
pgrep, pkill - look up or signal processes based on name and other attributes

Find out when your billion-second anniversary is (was).
Replace 12/31/1970 with your birth date.

Show a prettified list of nearby wireless APs

trace the system calls made by a process (and its children)
strace can be invaluable in trying to figure out what the heck some misbehaving program is doing. There are number of useful flags to limit and control its output, and to attach to already running programs. (See also 'ltrace'.)

list block devices
Shows all block devices in a tree with descruptions of what they are.

Fastest Sort. Sort Faster, Max Speed
sort is way slow by default. This tells sort to use a buffer equal to half of the available free memory. It also will use multiple process for the sort equal to the number of cpus on your machine (if greater than 1). For me, it is magnitudes faster. If you put this in your bash_profile or startup file, it will be set correctly when bash is started. $ sort -S1 --parallel=2 /dev/null && alias sortfast='sort -S$(($(sed '\''/MemF/!d;s/[^0-9]*//g'\'' /proc/meminfo)/2048)) $([ `nproc` -gt 1 ]&&echo -n --parallel=`nproc`)' Alternative $ echo|sort -S10M --parallel=2 &>/dev/null && alias sortfast="command sort -S$(($(sed '/MemT/!d;s/[^0-9]*//g' /proc/meminfo)/1024-200)) --parallel=$(($(command grep -c ^proc /proc/cpuinfo)*2))"

MPD + Digitally Imported
1.- Enter into the playlist path. 2.- Run the command. 3.- Playlists created!

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"

Url Encode
Converts reserved characters in a URI to their percent encoded counterparts. Alternate python version: $ echo "$url" | python -c 'import sys,urllib;print urllib.quote(sys.stdin.read().strip())'


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