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Reference: /n/sources/patch/applied/trampoline
Date: Mon Apr  5 23:22:13 CES 2004

--- /sys/man/8/trampoline	Thu Jan  1 00:00:00 1970
+++ /sys/man/8/trampoline	Mon Apr  5 23:22:13 2004
@@ -0,0 +1,54 @@
+.TH TRAMPOLINE 8
+.SH NAME
+trampoline \- forward incoming calls to another address
+.SH SYNOPSIS
+.B aux/trampoline
+[
+.B -m9
+]
+.I addr
+.RI [ netdir ]
+.SH DESCRIPTION
+.I Trampoline
+can be used in a service file (see
+.IR listen (8))
+to link an incoming call to
+another address that provides the service, typically on another machine.
+.PP
+.I Trampoline
+dials
+.I addr
+and copies data between that connection
+and its own standard input and output.
+Use the
+.B -9
+option if the connection carries only unencrypted 9P messages, to allow
+.I trampoline
+to size its buffer automatically.
+.PP
+Forwarding can be restricted to a particular calling machine,
+using the
+.B -m
+option.
+.I Netdir
+must be the incoming call directory.
+.I Trampoline
+finds the caller's MAC address
+.I m
+and checks that
+.IR ndb (6)
+contains an entry with
+.BI ether= m
+and the attribute
+.BR trampok .
+If no such entry is found, the call is rejected.
+.SH FILES
+.TF /sys/log/trampoline
+.TP
+.B /sys/log/trampoline
+logs rejected calls
+.SH SOURCE
+.B /sys/src/cmd/aux/trampoline.c
+.SH SEE ALSO
+.IR dial (2),
+.IR listen (8)