PROTOCOLS(5) BSD Reference Manual PROTOCOLS(5)
protocols - protocol name database
The protocols file contains information regarding the known protocols used in the DARPA Internet. For each protocol, a single line should be present with the following information: official protocol name protocol number aliases Items are separated by any number of blanks and/or tab characters. A hash mark ('#') indicates the beginning of a comment; subsequent char- acters up to the end of the line are not interpreted by the routines which search the file. Protocol names may contain any printable character other than a field delimiter, newline, or comment character.
/etc/protocols
getprotoent(3)
The protocols file format appeared in 4.2BSD.
A name server should be used instead of a static file. Lines in /etc/protocols are limited to BUFSIZ characters (currently 1024). Longer lines will be ignored. MirBSD #10-current June 5, 1993 1