1 files changed, 31 insertions, 0 deletions
diff --git a/sys/tty/ttyclear.x b/sys/tty/ttyclear.x
new file mode 100644
index 00000000..86dac6ff
--- /dev/null
+++ b/sys/tty/ttyclear.x
@@ -0,0 +1,31 @@
+# Copyright(c) 1986 Association of Universities for Research in Astronomy Inc.
+
+include	<chars.h>
+include	"tty.h"
+
+# TTYCLEAR -- Clear the terminal screen.
+
+procedure ttyclear (fd, tty)
+
+int	fd
+pointer	tty
+
+int	status
+bool	ttygetb()
+int	ttyctrl()
+errchk	ttygetb, ttyctrl
+
+begin
+	# If hardcopy terminal, output formfeed instead of clear.
+	if (ttygetb (tty, "ht"))
+	    status = ttyctrl (fd, tty, "ff", T_NLINES(tty))
+	else
+	    status = ERR
+	if (status == ERR)
+	    status = ttyctrl (fd, tty, "cl", T_NLINES(tty))
+
+	# If ff or cl capability not found, the best we can do is output
+	# a newline.
+	if (status == ERR)
+	    call putline (fd, "\n")
+end