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23 .TH DPIPE 1 "February 23, 2004" "Virtual Distributed Ethernet"
25 dpipe \- bi-directional pipe command
68 \fBdpipe\fP is a general tool to run two commands diverting the
69 standard output of the first command into the standard input of the second
71 It is the bi-directional
72 extension of the \fB|\fP (pipe) syntax used by all the shells.
73 The \fB=\fP has been chosen as a metaphore of two parallel communication lines
75 It is also possible to catenate several tools. Itermediate programs communicate
76 using standard input and stardard output with the preceding tool and alternate standard input
77 and output (respectively file descriptors number 3 and 4) towards the following tool.
78 If an intermediate tool should process only the data flowing in one direction
79 use \fB{\fP or \fB}\fP
80 as suffix for the preceding \fB=\fP and prefix of the following one.
82 This tool has been written as a tool for the Virtual Distributed Ethernet.
86 processes a and b are bidirectionally connected: stdin of a is connected to stdout of b
91 a and b are connected as above. alternate stdin of b is connected to stdout of c and
92 alternate stdout of b to stdin of c
96 This is a cycle of pipes: stdout of a is connected to stdin of b, stdout of b with stdin
97 of c, and stdout of c to stdin of a
99 .B dpipe a =} b }={ c {= d = e
101 all the notations can be mixed together.
102 this is a -> b -> d -> c and back to a; alternate ports of d are connected to e
112 VDE is a project by Renzo Davoli <renzo@cs.unibo.it>