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Common Development and Distribution License ("CDDL"), version 1.0.
You may only use this file in accordance with the terms of version
1.0 of the CDDL.
A full copy of the text of the CDDL should have accompanied this
source. A copy of the CDDL is also available via the Internet at
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Copyright (c) 2013, Joyent, Inc. All rights reserved.
cc [ flag ... ] file ... -lsocket -lnsl \ [ library ... ] #include <sys/types.h> #include <sys/socket.h> #include <ifaddrs.h>
int getifaddrs(struct ifaddrs **ifap);
void freeifaddrs(struct ifaddrs *ifp);
The getifaddrs() function is used to obtain the list of network interfaces on the local machine. A reference to a linked list of ifaddrs structures, as defined in <ifaddrs.h>, is stored in the memory referenced by ifap. Each structure in the list describes one network interface address, and is of the form:
struct ifaddrs {
struct ifaddrs *ifa_next;
char *ifa_name;
uint64_t ifa_flags;
struct sockaddr *ifa_addr;
struct sockaddr *ifa_netmask;
union {
struct sockaddr *ifu_broadaddr;
struct sockaddr *ifu_dstaddr;
} ifa_ifu;
void *ifa_data;
};
#define ifa_broadaddr ifa_ifu.ifu_broadaddr
#define ifa_dstaddr ifa_ifu.ifu_dstaddr
The list is traversed by following the ifa_next pointer. This member is NULL on the last structure in the list.
The ifa_name member contains the interface name.
The ifa_flags member contains the interface flags.
The ifa_addr member references the address of the interface. Use the sa_family member of this structure to determine the format of the address, as described in socket.h(3HEAD).
The ifa_netmask member references the netmask associated with ifa_addr, or NULL if one is not set.
If the IFF_BROADCAST bit is set in ifa_flags, then ifa_broadaddr is valid, or NULL if not present. If the IFF_POINTOPOINT bit is set, then ifa_dstaddr is valid, or NULL if not present. These two flags are mutually exclusive; see if_tcp(7P) for more information.
The ifa_data member is presently unused.
The memory used by getifaddrs() to back the list is dynamically allocated. It should be freed using freeifaddrs().
If successful, getifaddrs() returns the value 0; otherwise it returns -1 and sets errno to indicate the error.
The getifaddrs() function may fail and set errno for any of the errors specified for the library routines ioctl(2), socket(3SOCKET), and malloc(3C).
| ATTRIBUTE TYPE ATTRIBUTE VALUE |
| Interface Stability Committed |
| MT-Level MT-Safe |
ipadm(1M), ifconfig(1M), ioctl(2), malloc(3C), socket(3SOCKET), socket.h(3HEAD), if_tcp(7P), attributes(5)
On an illumos system, this function lists only interfaces with the IFF_UP flag set; see if_tcp(7P) and ifconfig(1M) for more information.
At present, this function only lists addresses from the AF_INET and AF_INET6 families. Other families, such as AF_LINK, are not included.