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.\"	@(#)rsh.1	8.2 (Berkeley) 4/29/95
.\"
.Dd March 9, 2005
.Dt RSH 1
.Os
.Sh NAME
.Nm rsh
.Nd remote shell
.Sh SYNOPSIS
.Nm
.Op Fl 46dn
.Op Fl l Ar username
.Op Fl p Ar port
.Ar host
.Op command
.Nm
.Op Fl 46dn
.Op Fl p Ar port
.Ar username@host
.Op command
.Sh DESCRIPTION
.Nm
executes
.Ar command
on
.Ar host .
.Pp
.Nm
copies its standard input to the remote command, the standard
output of the remote command to its standard output, and the
standard error of the remote command to its standard error.
Interrupt, quit and terminate signals are propagated to the remote
command;
.Nm
normally terminates when the remote command does.
The options are as follows:
.Bl -tag -width XlXusernameX
.It Fl 4
Use IPv4 addresses only.
.It Fl 6
Use IPv6 addresses only.
.It Fl d
The
.Fl d
option turns on socket debugging (using
.Xr setsockopt 2 )
on the
.Tn TCP
sockets used for communication with the remote host.
.It Fl l Ar username
By default, the remote username is the same as the local username.
The
.Fl l
option or the
.Ar username@host
format allow the remote name to be specified.
.It Fl n
The
.Fl n
option redirects input from the special device
.Pa /dev/null
(see the
.Sx BUGS
section of this manual page).
.It Fl p Ar port
Uses the given
.Pa port
instead of the one assigned to the service
.Dq shell .
May be given either as symbolic name or as number.
If no command is given, note that
.Xr rlogin 1
is started, which may need a different daemon
.No ( Xr rlogind 8
instead of
.Xr rshd 8 )
running on the server; you want to pass the
.Xr rshd 8
port number in that case.
.El
.Pp
If no
.Ar command
is specified, you will be logged in on the remote host using
.Xr rlogin 1 .
.Pp
Shell metacharacters which are not quoted are interpreted on local machine,
while quoted metacharacters are interpreted on the remote machine.
For example, the command
.Pp
.Dl rsh otherhost cat remotefile >> localfile
.Pp
appends the remote file
.Ar remotefile
to the local file
.Ar localfile ,
while
.Pp
.Dl rsh otherhost cat remotefile \&">>\&" other_remotefile
.Pp
appends
.Ar remotefile
to
.Ar other_remotefile .
.\" .Pp
.\" Many sites specify a large number of host names as commands in the
.\" directory
.\" .Pa /usr/hosts .
.\" If this directory is included in your search path, you can use the
.\" shorthand
.\" .Dq host command
.\" for the longer form
.\" .Dq rsh host command .
.Sh FILES
.Bl -tag -width /etc/hosts -compact
.It Pa /etc/hosts
.El
.Sh SEE ALSO
.Xr rcmd 1 ,
.Xr rlogin 1 ,
.Xr rcmd 3 ,
.Xr hosts.equiv 5 ,
.Xr rhosts 5 ,
.Xr environ 7
.Sh HISTORY
The
.Nm
command appeared in
.Bx 4.2 .
.Sh BUGS
If you are using
.Xr csh 1
and put a
.Nm
in the background without redirecting its input away from the terminal,
it will block even if no reads are posted by the remote command.
If no input is desired you should redirect the input of
.Nm
to
.Pa /dev/null
using the
.Fl n
option.
.Pp
You cannot run an interactive command (like
.Xr rogue 6
or
.Xr vi 1 )
using
.Nm ;
use
.Xr rlogin 1
instead.
.Pp
Stop signals stop the local
.Nm
process only; this is arguably wrong, but currently hard to fix for reasons
too complicated to explain here.