openbsd
diff --git a/src/cmd/acme/fsys.c b/src/cmd/acme/fsys.c
index 8e482f6..8393424 100644
--- a/src/cmd/acme/fsys.c
+++ b/src/cmd/acme/fsys.c
@@ -263,7 +263,12 @@
 fsysclose(void)
 {
 	closing = 1;
+	/*
+	 * apparently this is not kosher on openbsd.
+	 * perhaps because fsysproc is reading from sfd right now,
+	 * the close hangs indefinitely.
 	close(sfd);
+	 */
 }
 
 Xfid*