if_nameindex(3N)														  if_nameindex(3N)

NAME

       if_nameindex(), if_nametoindex(), if_indextoname(), if_freenameindex() - functions that map between an interface name and index value

SYNOPSIS

DESCRIPTION

       Interfaces  are	normally  known by names such as "lan0" and "vlan200."	The index is a unique positive integer value assigned to an inter-
       face. Index values start at 1, and 0 is not a valid index.

       This function maps an interface name into its corresponding
	      index.  If the specified interface name does not exist, the return value is set to 0 and is set to If there is a system  error,  the
	      return value is 0, and is set to the appropriate value.  For example, if the system is running out of memory, will be set to

       This function maps an interface index into its corresponding
	      name.   The  ifname  argument  must point to a buffer of at least bytes into which the interface name corresponding to the specified
	      index is returned.  This pointer is also the return value of the function.  is defined in and its value includes a terminating  null
	      byte  at	the end of the interface name.	If there is no interface corresponding to the specified index, NULL is returned and is set
	      to If there is a system error, the return value is 0, and is set to the appropriate value.

       This function returns all interface names and indexes as
	      an array of structures, one structure per interface.  The structure is defined in

	      struct if_nameindex {
		     unsigned int   if_index;  /* 1, 2, ... */
		     char	   *if_name;   /* null terminated name: "lan0" */
	      };

	      The end of the array of structures is indicated by a structure with an if_index of 0, and an if_name of NULL.  The function  returns
	      a NULL pointer upon an error, and would set to the appropriate value.

	      The  memory  used  for this array of structures along with the interface names pointed to by the if_name members is obtained dynami-
	      cally.  This memory is freed by the next function.

       This function frees the dynamic memory allocated by
	      The argument to this function must be a pointer that was returned by

CHANGE HISTORY

       The function prototypes and were defined in prior to HP-UX 11i v3.  They are now defined in

       Beginning with HP-UX 11i v3, these functions may pass on both IPv4 and IPv6 interfaces, and they no longer  reside  in  the  IPv6  library.
       They currently reside in the C library.	Therefore, applications using these functions no longer need to link with Applications using other
       IPv6 interfaces that reside in IPv6 library will need to continue to link with

AUTHOR

       and were developed by HP, IETF, and X/Open Company Limited.

ERRORS

       When or fails, the following error message is set in

       The specified interface or index does not exist.

SEE ALSO

       ndp(1M), inet6_opt_init(3N), inet6_rth_space(3N), ip6(7P), ndp(7P).

       RFC 3493 Basic Socket Interface Extensions for IPv6.

STANDARDS CONFORMANCE

																  if_nameindex(3N)