ref: 3fc055a3f967c9a56e93d4c6882b60c25609ebdc dir: /graveyard/hdup/
#!/bin/rc awk ' { if(a[n] != $1){ n++ a[n] = $1 a[n,1] = 0 s[$1] = $2 }else{ s[$1] = s[$1] " " $2 a[n,1] = 1 } } END{ for(i=1; i<n; i++){ if(a[i,1] == 1) print s[a[i]] } } ' $*