redirecting stdin in ksh

[Doug Gwyn <gwyn>]

> 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

My guess is that ksh closed down all fds other than 0,1,2
when execing a command inside the loop.