FreeBSD:网络接口信息

Question

我试图在FreeBSD中编程找到网络接口信息.在linux中,接口列在/ etc/network/interfaces文件中.

FreeBSD中有这样的文件吗？我该如何提取该信息？

Answer 1

你可以随时使用getifaddrs(3)这里是一个例子:

#include <stdio.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <ifaddrs.h>
int main(void) {
    struct ifaddrs *ifap,*ifa;
    getifaddrs(&ifap);
    for (ifa = ifap; ifa != NULL; ifa = ifa->ifa_next) {
        printf("%s\n",ifa->ifa_name);
    }
    freeifaddrs(ifap);
}

编辑:在Linux上,如果你需要获取接口的链接层地址,你需要找到AF_PACKET sa_family,它可以在linux上的netpacket/packet.h中找到,*bsd它的名字叫AF_LINK,它在net/if_dl.h中

#ifdef AF_LINK
#   include <net/if_dl.h>
#endif
#ifdef AF_PACKET
#   include <netpacket/packet.h>
#endif


#ifdef AF_LINK
    #define SDL ((struct sockaddr_dl *)ifa->ifa_addr)
    if (SDL->sdl_family == AF_LINK) {
        bcopy(SDL->sdl_data + SDL->sdl_nlen,....,SDL->sdl_alen
    }
    #undef SDL
#endif
#ifdef AF_PACKET
    if (ifa->ifa_addr->sa_family == AF_PACKET) {
        struct sockaddr_ll *sl = 
            (struct sockaddr_ll*) ifa->ifa_addr;

        bcopy(sl->sll_addr,....,sl->sll_halen
    }
#endif