protocols(4)							   File Formats 						      protocols(4)

NAME

       protocols - protocol name database

SYNOPSIS

       /etc/inet/protocols

       /etc/protocols

DESCRIPTION

       The  protocols  file   is a local source of information regarding the known protocols used in the DARPA Internet. The protocols file can be
       used in conjunction with or instead of other protocols sources, including the NIS maps ``protcols.byname'' and "protocols.bynumber" and the
       NIS+ table ``protocols''. Programs use the getprotobyname(3SOCKET) routine to access this information.

       The protocols file has one line for each protocol. The line has the following format:

	 official-protocol-name protocol-number aliases

       Items  are separated by any number of blanks and/or TAB characters. A `#' indicates the beginning of a comment; characters up to the end of
       the line are not interpreted by routines which search the file. Protocol names may contain any  printable  character  other  than  a  field
       delimiter, NEWLINE, or comment character.

EXAMPLES

       Example 1 A Sample Database

       The following is a sample database:

	 #
	 # Internet (IP) protocols
	 #
	 ip	     0	 IP	     # internet protocol, pseudo protocol number
	 icmp	     1	 ICMP	     # internet control message protocol
	 ggp	     3	 GGP	     # gateway-gateway protocol
	 tcp	     6	 TCP	     # transmission control protocol
	 egp	     8	 EGP	     # exterior gateway protocol
	 pup	     12  PUP	     # PARC universal packet protocol
	 udp	     17  UDP	     # user datagram protocol

	 #
	 # Internet (IPv6) extension headers
	 #
	 hopopt      0	 HOPOPT      # Hop-by-hop options for IPv6
	 ipv6	     41  IPv6	     # IPv6 in IP encapsulation
	 ipv6-route  43  IPv6-Route  # Routing header for IPv6
	 ipv6-frag   44  IPv6-Frag   # Fragment header for IPv6
	 esp	     50  ESP	     # Encap Security Payload for IPv6
	 ah	     51  AH	     # Authentication Header for IPv6
	 ipv6-icmp   58  IPv6-ICMP   # IPv6 internet control message protocol
	 ipv6-nonxt  59  IPv6-NoNxt  # No next header extension header for IPv6
	 ipv6-opts   60  IPv6-Opts   # Destination Options for IPv6

FILES

       /etc/nsswitch.conf    configuration file for name-service switch

SEE ALSO

       getprotobyname(3SOCKET), nsswitch.conf(4)

NOTES

       /etc/inet/protocols is the official SVR4 name of the protocols file.  The symbolic link /etc/protocols exists for BSD compatibility.

SunOS 5.11							    13 Jun 2002 						      protocols(4)