Index: res/res_agi.c
===================================================================
--- res/res_agi.c	(revision 40804)
+++ res/res_agi.c	(working copy)
@@ -2046,7 +2046,8 @@
 		agi.ctrl = fds[0];
 		agi.audio = efd;
 		res = run_agi(chan, argv[0], &agi, pid, dead);
-		close(fds[1]);
+		if (fds[1] != fds[0])
+			close(fds[1]);
 		if (efd > -1)
 			close(efd);
 	}