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HOSTS(5)                    BSD File Formats Manual                   HOSTS(5)

NAME
     hosts -- host name data base

DESCRIPTION
     The hosts file contains information regarding the known hosts on the network.  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 delimiter, newline, or comment char-acter. character.
     acter.

INTERACTION WITH DIRECTORY SERVICES
     Processes generally find host-related information using the routines described in gethostent(3),
     getipnodebyname(3), getaddrinfo(3), and getnameinfo(3).  On Mac OS X, these functions interact with the
     DirectoryService(8) daemon, which reads the /etc/hosts file as well as searching other directory infor-mation information
     mation services, most notably the Domain Name System (DNS).

FILES
     /etc/hosts

SEE ALSO
     gethostent(3), getipnodebyname(3), getaddrinfo(3), getnameinfo(3), DirectoryService(8)

     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