rtnetlink(3)               Library Functions Manual               rtnetlink(3)

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       rtnetlink - <?><?><?><?><?> <?><?><?><?><?> <?><?><?><?><?><?><?>
       <?><?><?><?><?> rtnetlink

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       <?><?><?><?><?> <?><?> <?><?><?><?><?><?><?><?><?> (libc<?> -lc)

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       #include <asm/types.h>
       #include <linux/netlink.h>
       #include <linux/rtnetlink.h>
       #include <sys/socket.h>

       rtnetlink_socket = socket(AF_NETLINK, int socket_type, NETLINK_ROUTE);

       int RTA_OK(struct rtattr *rta, int size);

       void *RTA_DATA(struct rtattr *rta);
       unsigned int RTA_PAYLOAD(struct rtattr *rta);

       struct rtattr *RTA_NEXT(struct rtattr *rta, unsigned int size);

       unsigned int RTA_LENGTH(unsigned int size);
       unsigned int RTA_SPACE(unsigned int size);

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       RTA_OK(rta, size) <?><?><?><?><?> <?><?><?><?><?><?> <?><?><?>
       <?><?><?> rta <?><?><?><?> <?><?><?> <?><?><?> <?><?><?><?><?>
       <?><?><?><?><?><?> size <?><?> <?><?><?><?><?> <?><?><?><?><?><?>
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       RTA_DATA(rta) <?><?><?><?><?> <?><?><?><?><?><?> <?><?><?>
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       RTA_PAYLOAD(rta) <?><?><?><?><?> <?><?><?> <?><?><?><?><?><?> <?><?><?>
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       RTA_NEXT(rta, size) <?><?><?><?> <?><?><?> <?><?><?><?><?>
       <?><?><?><?><?><?><?> <?><?><?> rta. <?><?><?><?><?><?><?> <?><?><?>
       <?><?><?><?><?><?><?> <?><?><?><?><?><?> size. <?><?><?>
       <?><?><?><?><?><?><?> RTA_OK <?><?><?><?><?><?> <?><?> <?><?><?>
       <?><?><?><?><?><?> <?><?><?><?><?><?><?>.

       RTA_LENGTH(size) <?><?><?><?><?> <?><?><?><?><?> <?><?><?><?><?><?><?>
       <?><?> size <?><?><?><?> <?><?> <?><?><?><?><?><?><?><?>
       <?><?><?><?><?><?><?><?> <?><?><?> <?><?><?><?><?>.

       RTA_SPACE(size) <?><?><?><?><?> <?><?><?><?><?> <?><?><?><?><?><?><?>
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       <?><?><?><?><?> <?><?><?><?><?> rtnetlink <?><?><?><?><?><?> MTU
       <?><?><?><?><?>:

           #include <linux/rtnetlink.h>

           ...

           struct {
               struct nlmsghdr  nh;
               struct ifinfomsg if;
               char             attrbuf[512];
           } req;

           struct rtattr *rta;
           unsigned int mtu = 1000;

           int rtnetlink_sk = socket(AF_NETLINK, SOCK_DGRAM, NETLINK_ROUTE);

           memset(&req, 0, sizeof(req));
           req.nh.nlmsg_len = NLMSG_LENGTH(sizeof(req.if));
           req.nh.nlmsg_flags = NLM_F_REQUEST;
           req.nh.nlmsg_type = RTM_NEWLINK;
           req.if.ifi_family = AF_UNSPEC;
           req.if.ifi_index = INTERFACE_INDEX;
           req.if.ifi_change = 0xffffffff; /* ??? */
           rta = (struct rtattr *) ((char *) &req +
                                    NLMSG_ALIGN(req.nh.nlmsg_len));
           rta->rta_type = IFLA_MTU;
           rta->rta_len = RTA_LENGTH(sizeof(mtu));
           req.nh.nlmsg_len = NLMSG_ALIGN(req.nh.nlmsg_len) +
                                         RTA_LENGTH(sizeof(mtu));
           memcpy(RTA_DATA(rta), &mtu, sizeof(mtu));
           send(rtnetlink_sk, &req, req.nh.nlmsg_len, 0);

<?><?><?><?> <?><?><?><?><?>
       netlink(3), netlink(7), rtnetlink(7)

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       <kde-l10n-ar@kde.org>.


<?><?><?><?><?> <?><?><?><?> <?><?><?><?><?> 6.18
                           8 <?><?><?><?><?><?> 2026              rtnetlink(3)