zmq4: router recv returns error when closing context

[speakyourcode]

No description provided.

[codecov-io]

Codecov Report

Merging #58 into master will increase coverage by 0.12%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master      #58      +/-   ##
==========================================
+ Coverage   54.37%   54.49%   +0.12%     
==========================================
  Files          26       26              
  Lines        1933     1934       +1     
==========================================
+ Hits         1051     1054       +3     
+ Misses        784      781       -3     
- Partials       98       99       +1

Impacted Files	Coverage Δ
router.go	75.59% <100%> (+0.98%)	⬆️
conn.go	54.73% <0%> (-1.06%)	⬇️
utils.go	75% <0%> (+10%)	⬆️

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[sbinet]

needs go-zeromq/license#3

[sbinet]

thanks for looking at this.

I have a couple of nit-picks but other than that, this looks fine.
(do I understand correctly that this also fixes #57 ?)

[sbinet]

I have cherry-picked your code and rebased over there: #72

thanks a lot.