One Liners

Unset (http) env vars

Only if you trust your environment, mind. $ eval $(env | grep -i http | sed 's/^/unset /; s/=.*//')

Core Count

cat /proc/cpuinfo | egrep "core id|physical id" | tr -d "\n" | sed s/physical/\\nphysical/g | grep -v ^$ | sort | uniq | wc -l

Socket Count

cat /proc/cpuinfo | grep "physical id" | sort | uniq | wc -l

Iterate through arrays in bash

for i in ${!ARR[@]}; do echo ${ARR[$i]}; done