diff --git a/src/os_unix.c b/src/os_unix.c
index d192b6b..9dde754 100644
--- a/src/os_unix.c
+++ b/src/os_unix.c
@@ -4806,6 +4806,11 @@
 		    // push stream discipline modules
 		    if (options & SHELL_COOKED)
 			setup_slavepty(pty_slave_fd);
+#  ifdef TIOCSCTTY
+		    // Try to become controlling tty (probably doesn't work,
+		    // unless run by root)
+		    ioctl(pty_slave_fd, TIOCSCTTY, (char *)NULL);
+#  endif
 		}
 # endif
 		set_default_child_environment(FALSE);