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== Survey (Everybody Votes)

image::../survey.png[Everybody Votes]

The surveyor pattern is used to send a timed survey out, responses
are individually returned until the survey has expired.  This pattern
is useful for service discovery and voting algorithms.

.survey.c
[source,c]
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include::src/survey.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 survey.c -lnng -o survey
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.Execution
[source,bash]
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include::src/survey.sh[]
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<1> The first survey times out with no responses because the clients aren’t connected yet.

.Output
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include::src/survey.out[]
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