hosts(5)

hosts5

Host name data base

Overview

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 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

Releases

163 releases since Mac OS X 10.0; the text changed 2 times.

  1. 10.0–10.4.11
  2. 10.5–10.6.8
  3. 10.7–26.5

History

The hosts file format appeared in 4.2BSD.

From files 974.120.2 in macOS 26.5. Parsed by carta from the page's mdoc source.