1.\" $OpenBSD: rcmdsh.3,v 1.16 2014/04/19 18:11:19 tedu Exp $ 2.\" 3.\" Copyright (c) 1983, 1991, 1993 4.\" The Regents of the University of California. All rights reserved. 5.\" 6.\" Redistribution and use in source and binary forms, with or without 7.\" modification, are permitted provided that the following conditions 8.\" are met: 9.\" 1. Redistributions of source code must retain the above copyright 10.\" notice, this list of conditions and the following disclaimer. 11.\" 2. Redistributions in binary form must reproduce the above copyright 12.\" notice, this list of conditions and the following disclaimer in the 13.\" documentation and/or other materials provided with the distribution. 14.\" 3. Neither the name of the University nor the names of its contributors 15.\" may be used to endorse or promote products derived from this software 16.\" without specific prior written permission. 17.\" 18.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 19.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 20.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 21.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 22.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 23.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 24.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 25.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 26.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 27.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 28.\" SUCH DAMAGE. 29.\" 30.Dd $Mdocdate: April 19 2014 $ 31.Dt RCMDSH 3 32.Os 33.Sh NAME 34.Nm rcmdsh 35.Nd return a stream to a remote command without superuser 36.Sh SYNOPSIS 37.In unistd.h 38.Ft int 39.Fn rcmdsh "char **ahost" "int inport" "const char *locuser" "const char *remuser" "const char *cmd" "char *rshprog" 40.Sh DESCRIPTION 41The 42.Fn rcmdsh 43function is used by normal users to execute a command on a remote machine 44using an authentication scheme based on reserved port numbers using 45.Xr ssh 1 46or the value of 47.Fa rshprog 48(if non-null). 49.Fa rshprog 50may be a fully-qualified path, a non-qualified command, or a command containing 51space-separated command line arguments. 52.Pp 53The 54.Fn rcmdsh 55function looks up the host 56.Fa *ahost 57using 58.Xr gethostbyname 3 , 59returning \-1 if the host does not exist. 60Otherwise 61.Fa *ahost 62is set to the standard name of the host and a connection is established to 63a server residing at the well-known Internet port 64.Li shell/tcp 65(or whatever port is used by 66.Fa rshprog ) . 67The parameter 68.Fa inport 69is ignored; it is only included to provide an interface similar to 70.Xr rcmd 3 . 71.Pp 72If the connection succeeds, a socket in the 73.Ux Ns -domain 74of type 75.Dv SOCK_STREAM 76is returned to the caller, and given to the remote 77command as stdin and stdout, and stderr. 78.Sh DIAGNOSTICS 79The 80.Fn rcmdsh 81function returns a valid socket descriptor on success. 82It returns \-1 on error and prints a diagnostic message on the standard error. 83.Sh SEE ALSO 84.Xr ssh 1 , 85.Xr socketpair 2 , 86.Xr rcmd 3 87.Sh HISTORY 88The 89.Fn rcmdsh 90function first appeared in 91.Ox 2.0 . 92.Sh BUGS 93If 94.Xr ssh 1 95encounters an error, a file descriptor is still returned instead of \-1. 96