1.\" $OpenBSD: rcmdsh.3,v 1.6 1999/07/05 04:41:00 aaron 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.\" $FreeBSD: src/lib/libc/net/rcmdsh.3,v 1.7 2007/01/09 00:28:02 imp Exp $ 31.\" 32.Dd December 31, 2017 33.Dt RCMDSH 3 34.Os 35.Sh NAME 36.Nm rcmdsh 37.Nd return a stream to a remote command without superuser 38.Sh LIBRARY 39.Lb libc 40.Sh SYNOPSIS 41.In unistd.h 42.Ft int 43.Fo rcmdsh 44.Fa "char **ahost" 45.Fa "int inport" 46.Fa "const char *locuser" 47.Fa "const char *remuser" 48.Fa "const char *cmd" 49.Fa "const char *rshprog" 50.Fc 51.Sh DESCRIPTION 52The 53.Fn rcmdsh 54function 55is used by normal users to execute a command on 56a remote machine using an authentication scheme based 57on reserved port numbers using 58.Xr rshd 8 Pq Pa net/bsdrcmds 59or the value of 60.Fa rshprog 61(if 62.No non- Ns Dv NULL ) . 63.Pp 64The 65.Fn rcmdsh 66function 67looks up the host 68.Fa *ahost 69using 70.Xr gethostbyname 3 , 71returning \-1 if the host does not exist. 72Otherwise 73.Fa *ahost 74is set to the standard name of the host 75and a connection is established to a server 76residing at the well-known Internet port 77.Dq Li shell/tcp 78(or whatever port is used by 79.Fa rshprog ) . 80The 81.Fa inport 82argument 83is ignored; it is only included to provide an interface similar to 84.Xr rcmd 3 . 85.Pp 86If the connection succeeds, 87a socket in the 88.Ux 89domain of type 90.Dv SOCK_STREAM 91is returned to the caller, and given to the remote 92command as 93.Dv stdin , stdout , 94and 95.Dv stderr . 96.Sh RETURN VALUES 97The 98.Fn rcmdsh 99function 100returns a valid socket descriptor on success. 101Otherwise, \-1 is returned 102and a diagnostic message is printed on the standard error. 103.Sh SEE ALSO 104.Xr rsh 1 Pq Pa net/bsdrcmds , 105.Xr socketpair 2 , 106.Xr rcmd 3 , 107.Xr rshd 8 108.Sh HISTORY 109The 110.Fn rcmdsh 111function first appeared in 112.Ox 2.0 , 113and made its way into 114.Fx 4.6 . 115.Sh BUGS 116If 117.Xr rsh 1 118encounters an error, a file descriptor is still returned instead of \-1. 119