redirecting stdin in ksh

[Charles Maurer]

While creating a shell script using ksh, I attempted to
redirect stdin for a series of reads from a file (See
"The Unix System" by S. Bourne, pg 212). The code goes
as follows:

more="yes"
exec 3<&0 < file	# dup stdin to fd 3, and redirect from file
while [ "$more" ]
do
	read number age name
	if [ "$?" -eq 0 ]
	then
		process number, age, name
	else 	# end of file
		more=""
	fi
done
exec 0<&3 3<&-		# redirect stdin back to fd 0, close fd 3

The input is redirected fine, but the script never regains
control from normal stdin.  When I "sh" the file, it works
as it should.  What should be done to achieve the same effect
through ksh?  I don't need to know alternative ways of accomplishing
the same thing.

Thanks in advance,

chip maurer
mtuni!chip