Amount of Memory
sysctl -a | grep hw.memsize:
or
/usr/sbin/system_profiler SPHardwareDataType | grep Memory
Amount of Swap
ls -al /private/var/vm/swapfile0 | awk '{print $5}'Amount of Free Swap
vm_stat | awk '/Pages free:/ {print substr($3,1,match($3,/\./)-1)}'