.TH OXPORT 4
.SH NAME
oxport \- export name space on a connection using Op
.SH SYNOPSIS
.B oxport
[
.B \-Ad
]
[
.B \-L
.I ms
]
[
.B \-x
.I addr
]
.I dir
.SH DESCRIPTION
.I Oxport
serves
a name space rooted at
.I dir
over a connection to an Op client. The connection is indeed
standard input, because the program is implemented to be used with
.IR listen (1).
Using
.I oxport
is more efficient in terms of latency than
using
.IR export (4)
for RTTs of 1ms or more.
.PP
The program does not
fork the current name space, any change to the current name space will
be visible to clients.
.PP
The connection is assumed to be trusted and authenticated, on the name of
the first user attaching to the exported file tree.
.PP
Flag
.B -x
can be used to make
.I oxport
dial
.I addr
and serve
.I dir
over the connection, after reporting the local system name to the other end. See
.IR ofs (4)
for the details. This is used in the octopus to export portions of terminals to the central PC.
In this case, the program authenticates and encrypts the connection, unless
.B -A
is given as an option.
.PP
Note that in the usual case of running
.I oxport
from
.I listen
it will not authenticate or encrypt the channel. That is assumed to be done by
.I listen
and not by this program.
.PP
Flag
.B -L
is used to debug the protocol by pretending that the RTT for a RPC is at least
.I ms
milliseconds for a message. The implementation is a call to
.IR sleep (2)
before attending each client request. Client requests are
served concurrently, thus this should not affect throughput.
.PP
See
.IR intro (O)
for a description of the protocol spoken. This is important if this program is being
used to export devices.
.SH EXAMPLE
Export (using Op) the entire file tree seen in the current name space
to clients connecting to
.B tcp!127.0.0.1!4242
(without authentication nor encryption of the communication channel, but with
debugging messages enabled):
.IP
.B "listen -At tcp!127.0.0.1!4242 oxport -d / >[2]/dev/cons"
.PP
Export our home directory to clients that authenticate, encrypting the communication
channel:
.IP
.B "listen -a rc4 -t tcp!127.0.0.1!10000 {o/oxport /usr/nemo}"
.PP
Export the directory
.B /term
to the Op client listening at the given address:
.IP
.B "o/oxport -x tcp!alboran!16699 /term"
.SH SOURCE
.B /usr/octopus/port/oxport.b
.SH SEE ALSO
.IR intro (O)
and
.IR ofs (4).
.SH BUGS
Currently,
.I oxport
denies access for subtrees of the directory exported
other than
.B /
(that is, it prevents the use of the field
.B path
in
.IR attach (O)
requests).