NAME    [Toc]    [Back]

       icmp - Internet Control Message Protocol

SYNOPSIS    [Toc]    [Back]

       #include <sys/socket.h> #include <netinet/in.h>

       The  following  is  the  socket call for sockets using the
       IPv4 address format:

       s = socket(AF_INET, SOCK_RAW, IPPROTO_ICMP);

       The following is the socket call  for  sockets  using  the
       IPv6 address format:

       s = socket(AF_INET6, SOCK_RAW, IPPROTO_ICMPV6);

DESCRIPTION    [Toc]    [Back]

       The  Internet Control Message Protocol (ICMP) is the error
       and control message protocol used by the Internet Protocol
       (IP) and the Internet Protocol family.  It may be accessed
       through a raw socket for network monitoring and diagnostic
       functions.  ICMP  sockets are connectionless, and are normally
 used with the  sendto()  and  recvfrom()  functions.
       The  connect() function may also be used to fix the destination
 for future packets, in which  case  the  read()  or
       recv() and write() or send() functions may be used.

       Outgoing packets automatically have an IP header prepended
       to them (based on the destination address). Incoming packets
 are received with the IP header and options intact.

ERRORS    [Toc]    [Back]

       If  a  socket  operation fails, errno may be set to one of
       the following values: The  socket  is  already  connected.
       This error occurs when trying to establish connection on a
       socket or when trying to send a datagram with the destination
  address  specified.   The  destination  address of a
       datagram was not specified, and the socket  has  not  been
       connected.   The  system ran out of memory for an internal
       data structure.  An attempt was made to  create  a  socket
       with  a  network  address  for  which no network interface
       exists.

SEE ALSO    [Toc]    [Back]

       Functions: send(2), recv(2)

       Files: netintro(7), inet(7), ip(7)

       RFC 792, Internet Control Message Protocol

       RFC 2463, Internet Control Message Protocol  (ICMPv6)  for
       the Internet Protocol Version 6 (IPv6)



                                                          icmp(7)