#command cdx cut -f 2 $TMP/aaa $TMP/bbb
#infile aaa
aaa	bbb	ccc
ddd	eee	fff
ggg	hhh	iii
#infile bbb
jjj	kkk	lll
mmm	nnn	ooo
ppp	qqq	rrr
#stdout
bbb
eee
hhh
kkk
nnn
qqq