protocols.4 (2010 09)

protocols(4) protocols(4)

NAME

protocols - protocol name database

DESCRIPTION

This ﬁle associates protocol numbers with ofﬁcial protocol names and aliases. This allows the user to

refer to a protocol by a symbolic name instead of a number. For each protocol, a single line should be

present with the following information:

<ofﬁcial protocol name> <ofﬁcial protocol number> <aliases>

These mappings are deﬁned in RFC 1700 Assigned Numbers.

Aliases are other names under which the protocol is also known. For example:

tcp 6 TCP

In this example, the library call getprotobyname()

can be invoked as:

p = getprotobyname("TCP");

instead of

p = getprotobyname("tcp");

Both produce the same results.

A line cannot start with a space. Items are separated by any number of blanks and/or tab characters. A

# character indicates the beginning of a comment. Characters from the # to the end of the line are not

interpreted by routines which search the ﬁle.

Protocol names can contain any printable character other than a white space, new-line, or comment char-

acter. Trailing blanks or tabs are allowed at the end of a line.

EXAMPLES

tcp 6 TCP # transmission control protocol

udp 17 UDP # user datagram protocol

AUTHOR

protocols was developed by the University of California, Berkeley.

FILES

/etc/protocols