diff --git a/options/linux/generic/pty-stubs.cpp b/options/linux/generic/pty-stubs.cpp
index d42aac66fb..c83d31a4bd 100644
--- a/options/linux/generic/pty-stubs.cpp
+++ b/options/linux/generic/pty-stubs.cpp
@@ -15,10 +15,6 @@
 int openpty(int *mfd, int *sfd, char *name, const struct termios *ios, const struct winsize *win) {
 	__ensure(!ios);
 
-	if (win) {
-		mlibc::infoLogger() << "mlibc: openpty ignores win argument" << frg::endlog;
-	}
-
 	int ptmx_fd;
 	if(int e = mlibc::sys_open("/dev/ptmx", O_RDWR | O_NOCTTY, 0, &ptmx_fd); e) {
 		errno = e;
@@ -38,6 +34,13 @@ int openpty(int *mfd, int *sfd, char *name, const struct termios *ios, const str
 		goto fail;
 	}
 
+	if(win) {
+		if(int ioctl_e, e = mlibc::sys_ioctl(ptmx_fd, TIOCSWINSZ, (void*)win, &ioctl_e); e || ioctl_e) {
+			errno = e;
+			goto fail;
+		}
+	}
+
 	*mfd = ptmx_fd;
 	*sfd = pts_fd;
 	return 0;
diff --git a/options/linux/include/mlibc/linux-sysdeps.hpp b/options/linux/include/mlibc/linux-sysdeps.hpp
index 36b20e1a82..903744c723 100644
--- a/options/linux/include/mlibc/linux-sysdeps.hpp
+++ b/options/linux/include/mlibc/linux-sysdeps.hpp
@@ -17,6 +17,7 @@ int sys_open(const char *pathname, int flags, mode_t mode, int *fd);
 int sys_close(int fd);
 int sys_read(int fd, void *buf, size_t count, ssize_t *bytes_read);
 int sys_write(int fd, const void *buf, size_t count, ssize_t *bytes_written);
+int sys_ioctl(int fd, unsigned long request, void *arg, int *result);
 
 [[gnu::weak]] int sys_dup2(int fd, int flags, int newfd);
 [[gnu::weak]] int sys_fork(pid_t *child);