linux c 获取网卡ip

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ifaddrs.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <sys/types.h>

void get_ip_addresses() {
    struct ifaddrs *ifaddr, *ifa;
    int family, s;

    if (getifaddrs(&ifaddr) == -1) {
        perror("getifaddrs");
        exit(EXIT_FAILURE);
    }

    for (ifa = ifaddr; ifa != NULL; ifa = ifa->ifa_next) {
        if (ifa->ifa_addr == NULL)
            continue;

        family = ifa->ifa_addr->sa_family;

        if (family == AF_INET) { // IPv4
            s = getnameinfo(ifa->ifa_addr,
                            sizeof(struct sockaddr_in),
                            ifa->ifa_name,
                            NI_MAXHOST,
                            NULL,
                            0,
                            NI_NUMERICHOST);
            if (s != 0) {
                printf("getnameinfo() failed: %s\n", gai_strerror(s));
                continue;
            }
            printf("%s: %s\n", ifa->ifa_name, ifa->ifa_name);
        }
    }

    freeifaddrs(ifaddr);
}

int main() {
    get_ip_addresses();
    return 0;
}