diff --git a/newlib/libc/sys/jehanne/ioctl.c b/newlib/libc/sys/jehanne/ioctl.c
index eec8832dd..a1cf3b481 100644
--- a/newlib/libc/sys/jehanne/ioctl.c
+++ b/newlib/libc/sys/jehanne/ioctl.c
@@ -17,13 +17,98 @@
  */
 #include <u.h>
 #include <libc.h>
+#include <envvars.h>
 #include <posix.h>
 #include <reent.h>
 #include <sys/ioctl.h>
+#include <errno.h>
 
+void
+tty_getsize(struct winsize *size)
+{
+	char *var;
+
+	var = jehanne_getenv("LINES");
+	if(var != nil){
+		size->ws_row = (unsigned short)atoi(var);
+		free(var);
+	} else {
+		size->ws_row = 0;
+	}
+	var = jehanne_getenv("COLS");
+	if(var != nil){
+		size->ws_col = (unsigned short)atoi(var);
+		free(var);
+	} else {
+		size->ws_row = 0;
+	}
+	var = jehanne_getenv("XPIXELS");
+	if(var != nil){
+		size->ws_xpixel = (unsigned short)atoi(var);
+		free(var);
+	} else {
+		size->ws_row = 0;
+	}
+	var = jehanne_getenv("YPIXELS");
+	if(var != nil){
+		size->ws_ypixel = (unsigned short)atoi(var);
+		free(var);
+	} else {
+		size->ws_row = 0;
+	}
+}
+int
+tty_setsize(struct winsize *size)
+{
+	int fd, i, s, w, h;
+	char buf[64];
+	struct winsize old;
+
+	if(size->ws_xpixel && size->ws_ypixel){
+PixelSized:
+		fd = open("/dev/wctl", OWRITE);
+		if(fd < 0)
+			return 0;
+		i = snprint(buf, sizeof(buf), "resize -dx %su -dy %su", size->ws_xpixel, size->ws_ypixel);
+		write(fd, buf, i);
+		close(fd);
+		return 1;
+	}
+	if(size->ws_row && size->ws_col){
+		tty_getsize(&old);
+		s = old.ws_xpixel / old.ws_col;
+		size->ws_xpixel = (s + 1)*size->ws_col;
+		s = old.ws_ypixel / old.ws_row;
+		size->ws_ypixel = (s + 1)*size->ws_row;
+		goto PixelSized;
+	}
+	return 0;
+}
 int
 ioctl(int fd, int request, ...)
 {
+	va_list ap;
+	void *parg;
+
+	int *errnop = &_REENT->_errno;
+	if(!POSIX_isatty(errnop, fd))
+		return -1;
+
+	va_start(ap, request);
+	switch(request){
+	case TIOCGWINSZ:
+		parg = va_arg(ap, void*);
+		tty_getsize(parg);
+		break;
+	case TIOCSWINSZ:
+		parg = va_arg(ap, void*);
+		if(!tty_setsize(parg))
+			*errnop = EPERM;
+		break;
+	default:
+		break;
+	}
+	va_end(ap);
 	// blatant lie
 	return 0;
 }
diff --git a/newlib/libc/sys/jehanne/sys/ioctl.h b/newlib/libc/sys/jehanne/sys/ioctl.h
index a1359cfb2..4ffa4a822 100644
--- a/newlib/libc/sys/jehanne/sys/ioctl.h
+++ b/newlib/libc/sys/jehanne/sys/ioctl.h
@@ -18,6 +18,17 @@
 #ifndef _SYS_IOCTL_H
 #define _SYS_IOCTL_H
 
+#define TIOCGWINSZ 1
+#define TIOCSWINSZ 2
+
+struct winsize {
+	unsigned short ws_row;
+	unsigned short ws_col;
+	unsigned short ws_xpixel;   /* unused */
+	unsigned short ws_ypixel;   /* unused */
+};
+
+
 int ioctl(int fd, int request, ...);
 
 #endif