diff --git a/lib/command.h b/lib/command.h
new file mode 100644
index 0000000..3009b26
--- /dev/null
+++ b/lib/command.h
@@ -0,0 +1,308 @@
+/*
+ * Zebra configuration command interface routine
+ * Copyright (C) 1997, 98 Kunihiro Ishiguro
+ *
+ * This file is part of GNU Zebra.
+ *
+ * GNU Zebra is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published
+ * by the Free Software Foundation; either version 2, or (at your
+ * option) any later version.
+ * 
+ * GNU Zebra is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with GNU Zebra; see the file COPYING.  If not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ */
+
+#ifndef _ZEBRA_COMMAND_H
+#define _ZEBRA_COMMAND_H
+
+#include "vector.h"
+#include "vty.h"
+
+/* Host configuration variable */
+struct host
+{
+  /* Host name of this router. */
+  char *name;
+
+  /* Password for vty interface. */
+  char *password;
+  char *password_encrypt;
+
+  /* Enable password */
+  char *enable;
+  char *enable_encrypt;
+
+  /* System wide terminal lines. */
+  int lines;
+
+  /* Log filename. */
+  char *logfile;
+
+  /* Log stdout. */
+  u_char log_stdout;
+
+  /* Log syslog. */
+  u_char log_syslog;
+  
+  /* config file name of this host */
+  char *config;
+
+  /* Flags for services */
+  int advanced;
+  int encrypt;
+
+  /* Banner configuration. */
+  char *motd;
+};
+
+/* There are some command levels which called from command node. */
+enum node_type 
+{
+  AUTH_NODE,			/* Authentication mode of vty interface. */
+  VIEW_NODE,			/* View node. Default mode of vty interface. */
+  AUTH_ENABLE_NODE,		/* Authentication mode for change enable. */
+  ENABLE_NODE,			/* Enable node. */
+  CONFIG_NODE,			/* Config node. Default mode of config file. */
+  DEBUG_NODE,			/* Debug node. */
+  AAA_NODE,			/* AAA node. */
+  KEYCHAIN_NODE,		/* Key-chain node. */
+  KEYCHAIN_KEY_NODE,		/* Key-chain key node. */
+  INTERFACE_NODE,		/* Interface mode node. */
+  ZEBRA_NODE,			/* zebra connection node. */
+  TABLE_NODE,			/* rtm_table selection node. */
+  RIP_NODE,			/* RIP protocol mode node. */ 
+  RIPNG_NODE,			/* RIPng protocol mode node. */
+  BGP_NODE,			/* BGP protocol mode which includes BGP4+ */
+  BGP_VPNV4_NODE,		/* BGP MPLS-VPN PE exchange. */
+  BGP_IPV4_NODE,		/* BGP IPv4 unicast address family.  */
+  BGP_IPV4M_NODE,		/* BGP IPv4 multicast address family.  */
+  BGP_IPV6_NODE,		/* BGP IPv6 address family */
+  OSPF_NODE,			/* OSPF protocol mode */
+  OSPF6_NODE,			/* OSPF protocol for IPv6 mode */
+  MASC_NODE,			/* MASC for multicast.  */
+  IRDP_NODE,			/* ICMP Router Discovery Protocol mode. */ 
+  IP_NODE,			/* Static ip route node. */
+  ACCESS_NODE,			/* Access list node. */
+  PREFIX_NODE,			/* Prefix list node. */
+  ACCESS_IPV6_NODE,		/* Access list node. */
+  PREFIX_IPV6_NODE,		/* Prefix list node. */
+  AS_LIST_NODE,			/* AS list node. */
+  COMMUNITY_LIST_NODE,		/* Community list node. */
+  RMAP_NODE,			/* Route map node. */
+  SMUX_NODE,			/* SNMP configuration node. */
+  DUMP_NODE,			/* Packet dump node. */
+  FORWARDING_NODE,		/* IP forwarding node. */
+  VTY_NODE			/* Vty node. */
+};
+
+/* Node which has some commands and prompt string and configuration
+   function pointer . */
+struct cmd_node 
+{
+  /* Node index. */
+  enum node_type node;		
+
+  /* Prompt character at vty interface. */
+  char *prompt;			
+
+  /* Is this node's configuration goes to vtysh ? */
+  int vtysh;
+  
+  /* Node's configuration write function */
+  int (*func) (struct vty *);
+
+  /* Vector of this node's command list. */
+  vector cmd_vector;	
+};
+
+/* Structure of command element. */
+struct cmd_element 
+{
+  char *string;			/* Command specification by string. */
+  int (*func) (struct cmd_element *, struct vty *, int, char **);
+  char *doc;			/* Documentation of this command. */
+  int daemon;                   /* Daemon to which this command belong. */
+  vector strvec;		/* Pointing out each description vector. */
+  int cmdsize;			/* Command index count. */
+  char *config;			/* Configuration string */
+  vector subconfig;		/* Sub configuration string */
+};
+
+/* Command description structure. */
+struct desc
+{
+  char *cmd;			/* Command string. */
+  char *str;			/* Command's description. */
+};
+
+/* Return value of the commands. */
+#define CMD_SUCCESS              0
+#define CMD_WARNING              1
+#define CMD_ERR_NO_MATCH         2
+#define CMD_ERR_AMBIGUOUS        3
+#define CMD_ERR_INCOMPLETE       4
+#define CMD_ERR_EXEED_ARGC_MAX   5
+#define CMD_ERR_NOTHING_TODO     6
+#define CMD_COMPLETE_FULL_MATCH  7
+#define CMD_COMPLETE_MATCH       8
+#define CMD_COMPLETE_LIST_MATCH  9
+#define CMD_SUCCESS_DAEMON      10
+
+/* Argc max counts. */
+#define CMD_ARGC_MAX   25
+
+/* Turn off these macros when uisng cpp with extract.pl */
+#ifndef VTYSH_EXTRACT_PL  
+
+/* DEFUN for vty command interafce. Little bit hacky ;-). */
+#define DEFUN(funcname, cmdname, cmdstr, helpstr) \
+  int funcname (struct cmd_element *, struct vty *, int, char **); \
+  struct cmd_element cmdname = \
+  { \
+    cmdstr, \
+    funcname, \
+    helpstr \
+  }; \
+  int funcname \
+  (struct cmd_element *self, struct vty *vty, int argc, char **argv)
+
+/* DEFUN_NOSH for commands that vtysh should ignore */
+#define DEFUN_NOSH(funcname, cmdname, cmdstr, helpstr) \
+  DEFUN(funcname, cmdname, cmdstr, helpstr)
+
+/* DEFSH for vtysh. */
+#define DEFSH(daemon, cmdname, cmdstr, helpstr) \
+  struct cmd_element cmdname = \
+  { \
+    cmdstr, \
+    NULL, \
+    helpstr, \
+    daemon \
+  }; \
+
+/* DEFUN + DEFSH */
+#define DEFUNSH(daemon, funcname, cmdname, cmdstr, helpstr) \
+  int funcname (struct cmd_element *, struct vty *, int, char **); \
+  struct cmd_element cmdname = \
+  { \
+    cmdstr, \
+    funcname, \
+    helpstr, \
+    daemon \
+  }; \
+  int funcname \
+  (struct cmd_element *self, struct vty *vty, int argc, char **argv)
+
+/* ALIAS macro which define existing command's alias. */
+#define ALIAS(funcname, cmdname, cmdstr, helpstr) \
+  struct cmd_element cmdname = \
+  { \
+    cmdstr, \
+    funcname, \
+    helpstr \
+  };
+
+#endif /* VTYSH_EXTRACT_PL */
+
+/* Some macroes */
+#define CMD_OPTION(S)   ((S[0]) == '[')
+#define CMD_VARIABLE(S) (((S[0]) >= 'A' && (S[0]) <= 'Z') || ((S[0]) == '<'))
+#define CMD_VARARG(S)   ((S[0]) == '.')
+#define CMD_RANGE(S)	((S[0] == '<'))
+
+#define CMD_IPV4(S)	   ((strcmp ((S), "A.B.C.D") == 0))
+#define CMD_IPV4_PREFIX(S) ((strcmp ((S), "A.B.C.D/M") == 0))
+#define CMD_IPV6(S)        ((strcmp ((S), "X:X::X:X") == 0))
+#define CMD_IPV6_PREFIX(S) ((strcmp ((S), "X:X::X:X/M") == 0))
+
+/* Common descriptions. */
+#define SHOW_STR "Show running system information\n"
+#define IP_STR "IP information\n"
+#define IPV6_STR "IPv6 information\n"
+#define NO_STR "Negate a command or set its defaults\n"
+#define CLEAR_STR "Reset functions\n"
+#define RIP_STR "RIP information\n"
+#define BGP_STR "BGP information\n"
+#define OSPF_STR "OSPF information\n"
+#define NEIGHBOR_STR "Specify neighbor router\n"
+#define DEBUG_STR "Debugging functions (see also 'undebug')\n"
+#define UNDEBUG_STR "Disable debugging functions (see also 'debug')\n"
+#define ROUTER_STR "Enable a routing process\n"
+#define AS_STR "AS number\n"
+#define MBGP_STR "MBGP information\n"
+#define MATCH_STR "Match values from routing table\n"
+#define SET_STR "Set values in destination routing protocol\n"
+#define OUT_STR "Filter outgoing routing updates\n"
+#define IN_STR  "Filter incoming routing updates\n"
+#define V4NOTATION_STR "specify by IPv4 address notation(e.g. 0.0.0.0)\n"
+#define OSPF6_NUMBER_STR "Specify by number\n"
+#define INTERFACE_STR "Interface infomation\n"
+#define IFNAME_STR "Interface name(e.g. ep0)\n"
+#define IP6_STR "IPv6 Information\n"
+#define OSPF6_STR "Open Shortest Path First (OSPF) for IPv6\n"
+#define OSPF6_ROUTER_STR "Enable a routing process\n"
+#define OSPF6_INSTANCE_STR "<1-65535> Instance ID\n"
+#define SECONDS_STR "<1-65535> Seconds\n"
+#define ROUTE_STR "Routing Table\n"
+#define PREFIX_LIST_STR "Build a prefix list\n"
+#define OSPF6_DUMP_TYPE_LIST \
+"(neighbor|interface|area|lsa|zebra|config|dbex|spf|route|lsdb|redistribute|hook|asbr|prefix|abr)"
+
+#define CONF_BACKUP_EXT ".sav"
+
+/* IPv4 only machine should not accept IPv6 address for peer's IP
+   address.  So we replace VTY command string like below. */
+#ifdef HAVE_IPV6
+#define NEIGHBOR_CMD       "neighbor (A.B.C.D|X:X::X:X) "
+#define NO_NEIGHBOR_CMD    "no neighbor (A.B.C.D|X:X::X:X) "
+#define NEIGHBOR_ADDR_STR  "Neighbor address\nIPv6 address\n"
+#define NEIGHBOR_CMD2      "neighbor (A.B.C.D|X:X::X:X|WORD) "
+#define NO_NEIGHBOR_CMD2   "no neighbor (A.B.C.D|X:X::X:X|WORD) "
+#define NEIGHBOR_ADDR_STR2 "Neighbor address\nNeighbor IPv6 address\nNeighbor tag\n"
+#else
+#define NEIGHBOR_CMD       "neighbor A.B.C.D "
+#define NO_NEIGHBOR_CMD    "no neighbor A.B.C.D "
+#define NEIGHBOR_ADDR_STR  "Neighbor address\n"
+#define NEIGHBOR_CMD2      "neighbor (A.B.C.D|WORD) "
+#define NO_NEIGHBOR_CMD2   "no neighbor (A.B.C.D|WORD) "
+#define NEIGHBOR_ADDR_STR2 "Neighbor address\nNeighbor tag\n"
+#endif /* HAVE_IPV6 */
+
+/* Prototypes. */
+void install_node (struct cmd_node *, int (*) (struct vty *));
+void install_default (enum node_type);
+void install_element (enum node_type, struct cmd_element *);
+void sort_node ();
+
+char *argv_concat (char **, int, int);
+vector cmd_make_strvec (char *);
+void cmd_free_strvec (vector);
+vector cmd_describe_command ();
+char **cmd_complete_command ();
+char *cmd_prompt (enum node_type);
+int config_from_file (struct vty *, FILE *);
+int cmd_execute_command (vector, struct vty *, struct cmd_element **);
+int cmd_execute_command_strict (vector, struct vty *, struct cmd_element **);
+void config_replace_string (struct cmd_element *, char *, ...);
+void cmd_init (int);
+
+/* Export typical functions. */
+extern struct cmd_element config_end_cmd;
+extern struct cmd_element config_exit_cmd;
+extern struct cmd_element config_quit_cmd;
+extern struct cmd_element config_help_cmd;
+extern struct cmd_element config_list_cmd;
+int config_exit (struct cmd_element *, struct vty *, int, char **);
+int config_help (struct cmd_element *, struct vty *, int, char **);
+char *host_config_file ();
+void host_config_set (char *);
+
+#endif /* _ZEBRA_COMMAND_H */