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DPIPE(1) DragonFly General Commands Manual DPIPE(1)
NAME
dpipe - bi-directional pipe command
SYNOPSIS
dpipe [ command [ args ] ] = [ command [ args ] ]
dpipe [ command [ args ] ] = [ command [ args ] ] [ = [ command [ args
] ] ] ...
DESCRIPTION
dpipe is a general tool to run two commands diverting the standard
output of the first command into the standard input of the second and
vice-versa. It is the bi-directional extension of the | (pipe) syntax
used by all the shells. The = has been chosen as a metaphor of two
parallel communication lines between the commands. It is also possible
to concatenate several tools. Intermediate programs communicate using
standard input and standard output with the preceding tool and
alternate standard input and output (respectively file descriptors
number 3 and 4) towards the following tool. If an intermediate tool
should process only the data flowing in one direction use { or } as
suffix for the preceding = and prefix of the following one.
This tool has been written as a tool for the Virtual Distributed
Ethernet.
EXAMPLE
dpipe a = b
processes a and b are bidirectionally connected: stdin of a is
connected to stdout of b and vice-versa
dpipe a = b = c
a and b are connected as above. Alternate stdin of b is connected to
stdout of c and alternate stdout of b to stdin of c
dpipe a =} b }= c
This is a cycle of pipes: stdout of a is connected to stdin of b,
stdout of b with stdin of c, and stdout of c to stdin of a
dpipe a =} b }={ c {= d = e
all the notations can be mixed together. this is a -> b -> d -> c and
back to a; alternate ports of d are connected to e
OPTIONS
no options.
NOTICE
Virtual Distributed Ethernet is not related in any way with www.vde.com
("Verband der Elektrotechnik, Elektronik und Informationstechnik" i.e.
the German "Association for Electrical, Electronic & Information
Technologies").
SEE ALSO
vde_switch(1), vde_plug(1), vde_plug2tap(1), vdeq(1). wirefilter(1).
AUTHOR
VDE is a project by Renzo Davoli <renzo@cs.unibo.it>.
Virtual Distributed Ethernet December 6, 2006 DPIPE(1)