#!/bin/bash
# list the intersection of attributes 
# found in a set of arff files
gawk '
	BEGIN        { IGNORECASE=1; OFS=","}
	FNR==1       { Files++ }
	/@attribute/ { Got[$2]++ }
	END          { for(A in Got)
                       if (Got[A]>=Files)
                           print  A
	}' $1