xforward(local)xforward(local)NAMExforward - provide user-level X forwarding service
SYNOPSISxforward [options]
OVERVIEWxforward provides a user-level X11 forwarding service which can be use‐
ful if there are IP network topologies which provide non-transitive
routing (e.g. routers which implement policy packet screening).
OPTIONS-display display
Specifies the destination display where the user wants applica‐
tions to appear. Without this argument, xforward will use the
DISPLAY environment variable.
-allow allowed-host1 [allowed-host2 ... allowed-host16]
Only connections from allowed-hosts are permitted. At least one
allowed-host must be specified, and at most sixteen are allowed.
DESCRIPTIONxforward will choose an unused port for the local display, and listen
for connections on the local host at that port. xforward informs the
user which port to use as the local display, when xforward is first
invoked. When it receives a connection, it will create a confirmation
pop-up on the destination. If the user confirms the connection
request, it will create a separate socket and connect it to the desti‐
nation, and then commence data piping between the two connections.
xforward can handle multiple simultaneous connections.
If there is no activity on a connection for 90 minutes, the connection
is closed. If the X server at the destination does not have access con‐
trol enabled, then xforward will report an error.
If a connection is closed by either end, any buffered data is drained
to its destination before xforward will close the corresponding socket
on the other end.
SEE ALSOsocket(2), connect(2), listen(2), accept(2), bind(2), select(2)BUGS
Out-of-band data is ignored/thrown away.
If the initial connection to the destination fails for some reason, the
client who connected to the local-display will get an open and immedi‐
ately closed TCP connection, which may cause indigestion to some pro‐
grams which expect some sort of server response or an error code indi‐
cating failure to connect.
AUTHORS
John Kohl, MIT Project Athena and Digital Equipment Corporation
Modifications for X by Win Treese and Alec Wolman, Digital Equipment
Corporation
DISTRIBUTION
The file NOTICE in the xforward distribution specifies the terms for
distributing xforward. The current version of xforward can be found by
anonymous FTP from crl.dec.com:/pub/DEC/xforward.tar.Z.
xforward(local)
