protocols(4)
NAME
protocols − protocol name data base
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>
These mappings are defined in RFC 1010 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 character. 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.
SEE ALSO
Hewlett-Packard Company — HP-UX Release 9.0: August 1992