.\"	$OpenBSD: rcmdsh.3,v 1.1 1996/09/01 21:25:35 millert Exp $
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.Dd Sep 1, 1996
.Dt RCMDSH 3
.Os OpenBSD
.Sh NAME
.Nm rcmd
.Nd return a stream to a remote command as unprivileged user
.Sh SYNOPSIS
.Fd #include <unistd.h>
.Ft int
.Fn rcmdsh "char **ahost" "int inport" "const char *locuser" "const char *remuser" "const char *cmd" "char *rshprog"
.Sh DESCRIPTION
The
.Fn rcmdsh
function
is used by normal users to execute a command on
a remote machine using an authentication scheme based
on reserved port numbers using
.Xr rshd 8
or the value of
.Fa rshprog
(if non-NULL).
.Pp
The
.Fn rcmdsh
function
looks up the host
.Fa *ahost
using
.Xr gethostbyname 3 ,
returning \-1 if the host does not exist.
Otherwise
.Fa *ahost
is set to the standard name of the host
and a connection is established to a server
residing at the well-known Internet port
.Li shell/tcp
(or whatever port is used by
.Fa rshprog
).  The parameter
.Fa inport
is ignored; it is only included to provide an interface similar to
.Xr rcmd 3 .
.Pp
If the connection succeeds,
a socket in the
.Tn UNIX
domain of type
.Dv SOCK_STREAM
is returned to the caller, and given to the remote
command as 
.Em stdin
and
.Em stdout ,
and
.Em stderr .
.Sh DIAGNOSTICS
The
.Fn rcmdsh
function
returns a valid socket descriptor on success.
It returns \-1 on error and prints a diagnostic message on the standard error.
.Sh SEE ALSO
.Xr rsh 1 ,
.Xr socketpair 2 ,
.Xr rcmd 3 ,
.Xr rshd 8
.Sh BUGS
If
.Xr rsh 1
gets an error a file descriptor is still returned instead of \-1.
.Sh HISTORY
The
.Fn rcmdsh
function first appeared in
.Bx Open .