diff --git a/include/vty/vty.h b/include/vty/vty.h
new file mode 100644
index 0000000..6df6b67
--- /dev/null
+++ b/include/vty/vty.h
@@ -0,0 +1,134 @@
+#ifndef _VTY_H
+#define _VTY_H
+
+#include <stdio.h>
+#include <stdarg.h>
+
+/* GCC have printf type attribute check.  */
+#ifdef __GNUC__
+#define PRINTF_ATTRIBUTE(a,b) __attribute__ ((__format__ (__printf__, a, b)))
+#else
+#define PRINTF_ATTRIBUTE(a,b)
+#endif				/* __GNUC__ */
+
+/* Does the I/O error indicate that the operation should be retried later? */
+#define ERRNO_IO_RETRY(EN) \
+	(((EN) == EAGAIN) || ((EN) == EWOULDBLOCK) || ((EN) == EINTR))
+
+/* Vty read buffer size. */
+#define VTY_READ_BUFSIZ 512
+
+#define VTY_BUFSIZ 512
+#define VTY_MAXHIST 20
+
+struct vty {
+	FILE *file;
+
+	/* File descripter of this vty. */
+	int fd;
+
+	/* Is this vty connect to file or not */
+	enum { VTY_TERM, VTY_FILE, VTY_SHELL, VTY_SHELL_SERV } type;
+
+	/* Node status of this vty */
+	int node;
+
+	/* Failure count */
+	int fail;
+
+	/* Output buffer. */
+	struct buffer *obuf;
+
+	/* Command input buffer */
+	char *buf;
+
+	/* Command cursor point */
+	int cp;
+
+	/* Command length */
+	int length;
+
+	/* Command max length. */
+	int max;
+
+	/* Histry of command */
+	char *hist[VTY_MAXHIST];
+
+	/* History lookup current point */
+	int hp;
+
+	/* History insert end point */
+	int hindex;
+
+	/* For current referencing point of interface, route-map,
+	   access-list etc... */
+	void *index;
+
+	/* For multiple level index treatment such as key chain and key. */
+	void *index_sub;
+
+	/* For escape character. */
+	unsigned char escape;
+
+	/* Current vty status. */
+	enum { VTY_NORMAL, VTY_CLOSE, VTY_MORE, VTY_MORELINE } status;
+
+	/* IAC handling: was the last character received the IAC
+	 * (interpret-as-command) escape character (and therefore the next
+	 * character will be the command code)?  Refer to Telnet RFC 854. */
+	unsigned char iac;
+
+	/* IAC SB (option subnegotiation) handling */
+	unsigned char iac_sb_in_progress;
+	/* At the moment, we care only about the NAWS (window size) negotiation,
+	 * and that requires just a 5-character buffer (RFC 1073):
+	 * <NAWS char> <16-bit width> <16-bit height> */
+#define TELNET_NAWS_SB_LEN 5
+	unsigned char sb_buf[TELNET_NAWS_SB_LEN];
+	/* How many subnegotiation characters have we received?  We just drop
+	 * those that do not fit in the buffer. */
+	size_t sb_len;
+
+	/* Window width/height. */
+	int width;
+	int height;
+
+	/* Configure lines. */
+	int lines;
+
+	int monitor;
+
+	/* In configure mode. */
+	int config;
+};
+
+/* Small macro to determine newline is newline only or linefeed needed. */
+#define VTY_NEWLINE  ((vty->type == VTY_TERM) ? "\r\n" : "\n")
+
+static inline char *vty_newline(struct vty *vty)
+{
+	return VTY_NEWLINE;
+}
+
+/* Prototypes. */
+void vty_init (void);
+void vty_init_vtysh (void);
+void vty_reset (void);
+struct vty *vty_new (void);
+struct vty *vty_create (int vty_sock);
+int vty_out (struct vty *, const char *, ...) PRINTF_ATTRIBUTE(2, 3);
+int vty_out_newline(struct vty *);
+int vty_read(struct vty *vty);
+void vty_read_config (char *, char *);
+void vty_time_print (struct vty *, int);
+void vty_close (struct vty *);
+char *vty_get_cwd (void);
+void vty_log (const char *level, const char *proto, const char *fmt, va_list);
+int vty_config_lock (struct vty *);
+int vty_config_unlock (struct vty *);
+int vty_shell (struct vty *);
+int vty_shell_serv (struct vty *);
+void vty_hello (struct vty *);
+
+
+#endif