rexec — return stream to a remote command
#define _BSD_SOURCE /* See feature_test_macros(7) */ #include <netdb.h>
int
rexec( |
char **ahost, |
| int inport, | |
| char *user, | |
| char *passwd, | |
| char *cmd, | |
int *fd2p); |
This interface is obsoleted by rcmd(3).
The rexec() function looks
up the host *ahost
using gethostbyname(3), returning
−1 if the host does not exist. Otherwise *ahost is set to the standard
name of the host. If a username and password are both
specified, then these are used to authenticate to the foreign
host; otherwise the environment and then the user's
.netrc file in his
home directory are searched for appropriate information. If
all this fails, the user is prompted for the information.
The port inport
specifies which well-known DARPA Internet port to use for the
connection; the call getservbyname("exec", "tcp") (see
getservent(3)) will return
a pointer to a structure that contains the necessary port.
The protocol for connection is described in detail in
rexecd(8).
If the connection succeeds, a socket in the Internet
domain of type SOCK_STREAM is
returned to the caller, and given to the remote command as
stdin and stdout. If fd2p is nonzero, then an
auxiliary channel to a control process will be setup, and a
descriptor for it will be placed in *fd2p. The control process will
return diagnostic output from the command (unit 2) on this
channel, and will also accept bytes on this channel as being
UNIX signal numbers, to be forwarded to the process group of
the command. The diagnostic information returned does not
include remote authorization failure, as the secondary
connection is set up after authorization has been verified.
If fd2p is 0, then
the stderr (unit 2 of the remote
command) will be made the same as the stdout and no provision is made for sending
arbitrary signals to the remote process, although you may be
able to get its attention by using out-of-band data.
Not in POSIX.1-2001. Present on the BSDs, Solaris, and
many other systems. The rexec()
function appeared in 4.2BSD.
The rexec() function sends
the unencrypted password across the network.
The underlying service is considered a big security hole and therefore not enabled on many sites, see rexecd(8) for explanations.
This page is part of release 3.33 of the Linux man-pages project. A
description of the project, and information about reporting
bugs, can be found at http://man7.org/linux/man-pages/.
|
Copyright (c) 1983, 1991, 1993 The Regents of the University of California. All rights reserved. Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met: 1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer. 2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution. 3. All advertising materials mentioning features or use of this software must display the following acknowledgement: This product includes software developed by the University of California, Berkeley and its contributors. 4. Neither the name of the University nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission. THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. (#)rexec.3 8.1 (Berkeley) 6/4/93 $FreeBSD: src/lib/libcompat/4.3/rexec.3,v 1.12 2004/07/02 23:52:14 ru Exp $ Taken from FreeBSD 5.4; not checked against Linux reality (mtk) 2007-12-08, mtk, Converted from mdoc to man macros |