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.\" $FreeBSD: src/share/man/man5/hosts.equiv.5,v 1.10.2.6 2002/02/01 15:51:18 ru Exp $
.\"
.Dd December 31, 2017
.Dt HOSTS.EQUIV 5
.Os
.Sh NAME
.Nm hosts.equiv ,
.Nm .rhosts
.Nd trusted remote host and user name data base
.Sh DESCRIPTION
The
.Nm
and
.Nm .rhosts
files contain information regarding
trusted hosts and users on the network.
For each host a single line should be present
with the following information:
.Pp
simple
.Bd -unfilled -offset indent
hostname [username]
.Ed
.Pp
or the more verbose
.Bd -unfilled -offset indent
[+-][hostname|@netgroup] [[+-][username|@netgroup]]
.Ed
.Pp
A
.Dq @
indicates a host by netgroup or user by netgroup.
A single
.Dq +
matches all hosts or users.  A host name with a leading
.Dq -
will reject
all matching hosts and all their users.
A user name with leading
.Dq -
will reject all matching users from matching hosts.
.Pp
Items are separated by any number of blanks and/or
tab characters.  A
.Dq #
indicates the beginning of
a comment; characters up to the end of the line are
not interpreted by routines which search the file.
.Pp
Host names are specified in the conventional
.Dq .\&
(dot) notation using the
.Xr inet_addr 3
routine
from the Internet address manipulation library,
.Xr inet 3 .
Host names may contain any printable
character other than a field delimiter, newline,
or comment character.
.Pp
For security reasons, a user's
.Nm .rhosts
file will be ignored if it is not a regular file, or if it
is not owned by the user, or
if it is writable by anyone other than the user.
.Sh FILES
.Bl -tag -width /etc/hosts.equivxxx -compact
.It Pa /etc/hosts.equiv
The
.Nm
file resides in
.Pa /etc .
.It Pa $HOME/.rhosts
.Nm .rhosts
file resides in
.Pa $HOME .
.El
.Sh EXAMPLES
.Dl bar.com foo
.Pp
Trust user
.Dq foo
from host
.Dq bar.com .
.Pp
.Dl +@allclient
.Pp
Trust all hosts from netgroup
.Dq allclient .
.Pp
.Dl +@allclient -@dau
.Pp
Trust all hosts from netgroup
.Dq allclient
and their users
except users from netgroup
.Dq dau .
.Sh SEE ALSO
.Xr rcp 1 Pq Pa net/bsdrcmds ,
.Xr rlogin 1 Pq Pa net/bsdrcmds ,
.Xr rsh 1 Pq Pa net/bsdrcmds ,
.Xr gethostbyname 3 ,
.Xr inet 3 ,
.Xr innetgr 3 ,
.Xr ruserok 3 ,
.Xr ifconfig 8 ,
.Xr named 8 ,
.Xr yp 8
.Sh BUGS
This man page is incomplete.
For more information read
the source in
.Pa src/lib/libc/net/rcmd.c
or the SunOS man page.