ref: 4696de84b4553d33d2bc1649a55d303c1788a41b
dir: /sys/src/cmd/dict/getneeds/
#!/bin/rc
for (x in spec tag aux status) {
	grep ' '^$x^' ' $1 > junk1
	sort +4 -5 +3n -4 junk1 > junk2
	awk '{if ($5 != prev) print $0; prev = $5}' junk2 > junk3
	sort -n +2 -3 junk3 > need$x
	rm junk*
}