NAME    [Toc]    [Back]

       protocols  -  Defines  the  Internet protocols used on the
       local host

SYNOPSIS    [Toc]    [Back]

       /etc/protocols

DESCRIPTION    [Toc]    [Back]

       The /etc/protocols file  contains  information  about  the
       known  protocols  used  in the Internet.  Each protocol is
       represented by a single line in the protocols file.   Each
       entry is of the form:

       Name Number Aliases

       The  fields  contain  the  following information: Official
       Internet  protocol  name.   Protocol  number.   Unofficial
       names used for the protocol.

       Items on a line are separated by one or more spaces or tab
       characters.  Comments begin with the # (number sign),  and
       routines  that  search the protocols file do not interpret
       characters from the beginning of a comment to the  end  of
       the line.  A protocol name can contain any printable character
 except a field delimiter, newline character, or comment
 character.

       The lines in the file appear as follows:

       #  #  Internet  (IP) protocols # ip      0    IP         #
       internet  protocol,  pseudo  protocol  number  icmp      1
       ICMP        #  internet control message protocol igmp    2
       IGMP       # internet group management protocol ggp      3
       GGP         #  gateway-gateway  protocol  tcp     6    TCP
       # transmission control protocol pup     12   PUP         #
       PARC  universal  packet protocol udp     17   UDP        #
       user  datagram  protocol  hopopt             0      HOPOPT
       #  hop-by-hop  options for ipv6 ipv6            41    IPV6
       # ipv6 ipv6-route      43    IPV6-ROUTE         #  routing
       header  for ipv6 ipv6-frag       44    IPV6-FRAG         #
       fragment  header  for  ipv6  esp               50      ESP
       #  encapsulating security payload ah              51    AH
       # authentication header  ipv6-icmp        58     IPV6-ICMP
       #  icmp for ipv6 ipv6-nonxt      59    IPV6-NONXT        #
       no next header for ipv6  ipv6-opts        60     IPV6-OPTS
       # destination options for ipv6.oE

SEE ALSO    [Toc]    [Back]

       Functions:  endprotoent(3),  getprotobyname(3),  getprotobynumber(3), getprotoent(3), setprotoent(3)



                                                     protocols(4)