OSF

NAME

protocols − Defines the Internet protocols used on the local host

SYNOPSIS

/etc/protocols

DESCRIPTION

The /etc/protocols file contains information about the known protocols used in the DARPA (Defense Advanced Research Projects Agency) 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:

NameOfficial Internet protocol name. 

NumberProtocol number. 

AliasesUnofficial 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
#@(#)protocols5.1 (Berkeley) 4/17/90
#
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
hmp     20   HMP        # host monitoring protocol
xns-idp 22   XNS-IDP    # Xerox NS IDP
rdp     27   RDP        # "reliable datagram" protocol

RELATED INFORMATION

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