IPV6_MTU(2const) — Linux manual page

IPV6_MTU(2const)                                         IPV6_MTU(2const)

NAME         top

       IPV6_MTU - path maximum transmission unit size

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_IPV6, IPV6_MTU,
                      const int *val, sizeof(int));
       int getsockopt(int sockfd, IPPROTO_IPV6, IPV6_MTU,
                      int *val, sizeof(int));

DESCRIPTION         top

       getsockopt():
              Retrieve the current known path MTU of the current socket.
              Valid only when the socket has been connected.

       setsockopt():
              Set the MTU to be used for the socket.  The MTU is limited
              by the device MTU or the path MTU when path MTU discovery
              is enabled.

ERRORS         top

       See IPPROTO_IPV6(2const).  See setsockopt(2).  See ipv6(7).

SEE ALSO         top

       IPPROTO_IPV6(2const), setsockopt(2), ipv6(7)

COLOPHON         top

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Linux man-pages 6.18            2025-12-02               IPV6_MTU(2const)

Pages that refer to this page: IPPROTO_IPV6(2const)

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