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28 .\" @(#)hosts.5 8.2 (Berkeley) 12/11/93
31 .Dd September 15, 2022
36 .Nd host name data base
40 file contains information regarding
41 the known hosts on the network.
42 It can be used in conjunction with DNS, and the NIS
43 maps `hosts.byaddr' and `hosts.byname', as controlled by
45 For each host a single line should be present
46 with the following information:
47 .Bd -unfilled -offset indent
53 Items are separated by any number of blanks and/or
55 A ``#'' indicates the beginning of
56 a comment; characters up to the end of the line are
57 not interpreted by routines which search the file.
59 This file provides a backup used when the name server
61 For the name server, it is suggested that only a few addresses
62 be included in this file.
63 These include addresses for the local interfaces that
65 needs at boot time and a few machines on the local network.
67 Network addresses are specified in either the conventional
68 ``.'' (dot) notation for IPv4 or colon hexadecimal notation for IPv6,
72 from the Internet address manipulation library,
74 Host names may contain any printable
75 character other than a field delimiter, newline,
78 .Bl -tag -width /etc/hosts -compact
93 file format appeared in