C++ 对比前n个字符并返回指向=后面的char 指针

定义一个字符指针数组
char *mParams[NL_PARAMS_MAX];
用asprintf格式化字符串

asprintf(&mParams[0], "ADDRESS=%s/%d", addrstr, ifaddr->ifa_prefixlen);
asprintf(&mParams[1], "INTERFACE=%s", ifname);
asprintf(&mParams[2], "FLAGS=%u", ifaddr->ifa_flags);
asprintf(&mParams[3], "SCOPE=%u", ifaddr->ifa_scope);
asprintf(&mParams[4], "IFINDEX=%u", ifaddr->ifa_index);

const char *NetlinkEvent::findParam(const char *paramName) {
    size_t len = strlen(paramName);
    for (int i = 0; i < NL_PARAMS_MAX && mParams[i] != NULL; ++i) {
        const char *ptr = mParams[i] + len;
        if (!strncmp(mParams[i], paramName, len) && *ptr == '=')
            return ++ptr;
    }
    SLOGE("NetlinkEvent::FindParam(): Parameter '%s' not found", paramName);
    return NULL;
}

注意asprint 使用完需要释放

 for (i = 0; i < NL_PARAMS_MAX; i++) {
        if (!mParams[i])
            break;
        free(mParams[i]);
    }

asprintf介绍