IP_RECVTTL(2const) — Linux manual page

IP_RECVTTL(2const)                                     IP_RECVTTL(2const)

NAME         top

       IP_RECVTTL - enable IP_TTL control message

LIBRARY         top

       Standard C library (libc, -lc)

SYNOPSIS         top

       #include <netinet/in.h>  /* Definition of IP* constants */
       #include <sys/socket.h>

       int setsockopt(int sockfd, IPPROTO_IP, int opt,
                      const int *enable, sizeof(int));

DESCRIPTION         top

       When this flag is set, pass a IP_TTL(2const) control message with
       the time-to-live field of the received packet as a 32 bit integer.

       Not supported for SOCK_STREAM sockets.

ERRORS         top

       See IPPROTO_IP(2const).  See setsockopt(2).  See ip(7).

VERSIONS         top

       Some BSD sockets implementations also provide an IP_RECVTTL
       option, but an ancillary message with type IP_RECVTTL is passed
       with the incoming packet.  This is different from the
       IP_TTL(2const) option used in Linux.

HISTORY         top

       Linux 2.2.

SEE ALSO         top

       IPPROTO_IP(2const), setsockopt(2), ip(7)

COLOPHON         top

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Linux man-pages 6.18            2025-11-25             IP_RECVTTL(2const)

Pages that refer to this page: IPPROTO_IP(2const)

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