Work around ancient shells where >$3 does not implicitly quote $3.

Also add an entry in shelltest.od to reject any shell exhibiting that
bug.

Reported-by: Wayne Scott <wsc9tt@gmail.com>

docs/cookbook/c/hello world.list.od

@@ -23,6 +23,6 @@ redo-ifchange "$S/sources"
 	done | uniq
 
 	printf '%s\n' "$LIBGTK2" "$LIBQT4"
-) >$3
+) >"$3"
 
-redo-stamp <$3
+redo-stamp <"$3"

t/shelltest.od

@@ -522,6 +522,18 @@ x2=$(cd shlink && basename "$(pwd -L)")
 [ "$x1" = "t" ] || fail 122
 [ "$x2" = "shlink" ] || fail 123
 
+# Reported by Wayne Scott on FreeBSD 7.0 (ancient). Apparently the sh (or
+# bash?) there prints "$3: ambiguous redirect" if you redirect to it without
+# putting the $3 in quotes (ie >"$3").  I hadn't seen that before, even
+# though it's not obvious to most sh users that the > argument is implicitly
+# quoted.
+set a b "shelltest.tmp log.tmp"
+rm -f "$3" $3
+echo hello >$3 || fail 130
+[ -e "$3" ] || fail 131
+[ ! -e "shelltest.tmp" ] || fail 132
+rm -f "$3" $3
+
 [ -e shelltest.failed ] && exit 41
 [ -e shelltest.warned ] && exit 42
 exit 40