HOSTS(5) BSD File Formats Manual HOSTS(5)NAMEhosts — host name data base
DESCRIPTION
The hosts file contains information regarding the known hosts on the net‐
work. For each host a single line should be present with the following
information:
Internet address
Official host name
Aliases
Items are separated by any number of blanks and/or tab characters. A
``#'' indicates the beginning of a comment; characters up to the end of
the line are not interpreted by routines which search the file.
Network addresses may either be specified for IP version 4 or version 6.
IP version 4 addresses are specified in the conventional dotted address
notation. IP version 6 addresses are specified using the colon-separated
notation described in RFC1924.
Host names may contain any printable character other than a field delim‐
iter, newline, or comment character.
The hosts file is read by mDNSResponder(8) and used to supply results for
calls to getaddrinfo(3), getnameinfo(3), etc. in addition to results
obtained from multicast and unicast DNS.
FILES
/etc/hosts
SEE ALSOgethostent(3), getipnodebyname(3), getaddrinfo(3), getnameinfo(3)
RFC1924: A Compact Representation of IPv6 Addresses.
HISTORY
The hosts file format appeared in 4.2BSD.
4.2 Berkeley Distribution December 11, 1993 4.2 Berkeley Distribution
