src/cmd/index/final.sort - plan9 - Git at Google

 # final.sort
 #   Input/Output: sort key (tab) string (tab) numlist
 #   Sort by $1 (string)

 sort -t'	' +0fd -1 +0f -1 $*
	# final.sort
	# Input/Output: sort key (tab) string (tab) numlist
	# Sort by $1 (string)

	sort -t' ' +0fd -1 +0f -1 $*