JAPH(just another perl approach),hehe: 
perl -e 'map{chomp;$a[$i<3?$i:($i=0)].=$_;$i++}<>;print"@a\n";' filea 
+fileb filec

[download]
assumption that each file has the same number of lines, here line=3 for ease

In reply to Re: parallel reading by whyxys
in thread parallel reading by azaria

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