| /* ifaddrs.h -- declarations for getting network interface addresses |
| Copyright (C) 2002 Free Software Foundation, Inc. |
| This file is part of the GNU C Library. |
| |
| The GNU C Library is free software; you can redistribute it and/or |
| modify it under the terms of the GNU Lesser General Public |
| License as published by the Free Software Foundation; either |
| version 2.1 of the License, or (at your option) any later version. |
| |
| The GNU C Library 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 |
| Lesser General Public License for more details. |
| |
| You should have received a copy of the GNU Lesser General Public |
| License along with the GNU C Library; if not, see |
| <http://www.gnu.org/licenses/>. */ |
| |
| #ifndef _IFADDRS_H |
| #define _IFADDRS_H 1 |
| |
| #include <features.h> |
| #include <sys/socket.h> |
| |
| __BEGIN_DECLS |
| |
| /* The `getifaddrs' function generates a linked list of these structures. |
| Each element of the list describes one network interface. */ |
| struct ifaddrs |
| { |
| struct ifaddrs *ifa_next; /* Pointer to the next structure. */ |
| |
| char *ifa_name; /* Name of this network interface. */ |
| unsigned int ifa_flags; /* Flags as from SIOCGIFFLAGS ioctl. */ |
| |
| struct sockaddr *ifa_addr; /* Network address of this interface. */ |
| struct sockaddr *ifa_netmask; /* Netmask of this interface. */ |
| union |
| { |
| /* At most one of the following two is valid. If the IFF_BROADCAST |
| bit is set in `ifa_flags', then `ifa_broadaddr' is valid. If the |
| IFF_POINTOPOINT bit is set, then `ifa_dstaddr' is valid. |
| It is never the case that both these bits are set at once. */ |
| struct sockaddr *ifu_broadaddr; /* Broadcast address of this interface. */ |
| struct sockaddr *ifu_dstaddr; /* Point-to-point destination address. */ |
| } ifa_ifu; |
| /* These very same macros are defined by <net/if.h> for `struct ifaddr'. |
| So if they are defined already, the existing definitions will be fine. */ |
| # ifndef ifa_broadaddr |
| # define ifa_broadaddr ifa_ifu.ifu_broadaddr |
| # endif |
| # ifndef ifa_dstaddr |
| # define ifa_dstaddr ifa_ifu.ifu_dstaddr |
| # endif |
| |
| void *ifa_data; /* Address-specific data (may be unused). */ |
| }; |
| |
| |
| /* Create a linked list of `struct ifaddrs' structures, one for each |
| network interface on the host machine. If successful, store the |
| list in *IFAP and return 0. On errors, return -1 and set `errno'. |
| |
| The storage returned in *IFAP is allocated dynamically and can |
| only be properly freed by passing it to `freeifaddrs'. */ |
| extern int getifaddrs (struct ifaddrs **__ifap) __THROW; |
| |
| /* Reclaim the storage allocated by a previous `getifaddrs' call. */ |
| extern void freeifaddrs (struct ifaddrs *__ifa) __THROW; |
| |
| __END_DECLS |
| |
| #endif /* ifaddrs.h */ |