use $(<file) instead of $(cat file) since this script uses ksh; ok ajacoutot@

src/etc/rc

@@ -1,4 +1,4 @@
-#	$OpenBSD: rc,v 1.540 2019/11/06 16:26:24 deraadt Exp $
+#	$OpenBSD: rc,v 1.541 2019/11/10 15:02:36 naddy Exp $
 
 # System startup script run by init on autoboot or after single-user.
 # Output and error are redirected to console by init, and the console is the
@@ -220,7 +220,7 @@ reorder_libs() {
 			$_install /usr/libexec/ld.so /usr/libexec/ld.so.save
 			$_install ld.so.test $_lib_dir/ld.so
 		else
-			cc -shared -o $_lib $(ls *.so | sort -R) $(cat .ldadd)
+			cc -shared -o $_lib $(ls *.so | sort -R) $(<.ldadd)
 			[[ -s $_lib ]] && file $_lib | fgrep -q 'shared object'
 			LD_BIND_NOW=1 LD_LIBRARY_PATH=$_tmpdir awk 'BEGIN {exit 0}'
 			LD_BIND_NOW=1 LD_LIBRARY_PATH=$_tmpdir openssl \
@@ -389,7 +389,7 @@ ttyflags -a
 
 # Set keyboard encoding.
 if [[ -x /sbin/kbd && -s /etc/kbdtype ]]; then
-	kbd "$(cat /etc/kbdtype)"
+	kbd "$(</etc/kbdtype)"
 fi
 
 wsconsctl_conf