Fix conversion specification to match the parameters
$flags defaults to 0 for nn_send + nn_recv
Merge branch 'bz/flags-defaults-to-zero'

* bz/flags-defaults-to-zero:
  $flags defaults to 0 for nn_send + nn_recv
Merge branch 'bz/fix-printf-args'

* bz/fix-printf-args:
  Fix conversion specification to match the parameters