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== Pipeline (A One-Way Pipe)

image::pipeline.png[A One-Way Pipe]

This pattern is useful for solving producer/consumer problems, including
load-balancing.  Messages flow from the push side to the pull side.  If
multiple peers are connected, the pattern attempts to distribute fairly.

.pipeline.c
[source,C]
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include::src/pipeline.c[]
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<1> Blithely assumes message is ASCIIZ string. Real code should check it.

.Compilation
[source,bash]
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gcc pipeline.c -lnanomsg -o pipeline
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.Execution
[source,bash]
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./pipeline node0 ipc:///tmp/pipeline.ipc & node0=$! && sleep 1
./pipeline node1 ipc:///tmp/pipeline.ipc "Hello, World!"
./pipeline node1 ipc:///tmp/pipeline.ipc "Goodbye."
kill $node0
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.Output
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NODE1: SENDING "Hello, World!"
NODE0: RECEIVED "Hello, World!"
NODE1: SENDING "Goodbye."
NODE0: RECEIVED "Goodbye."
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