Blank lines / "(no name)" in output of ros2 node list #72
Description
Not a major issue but something we should look into eventually:
built from source with fastrtps on linux:
<ros2 run demo_nodes_cpp add_two_ints_server>
dhood@osrf-esteve:~/ros2_ardent [ros2_ardent]$ ros2 node list
add_two_ints_server
<kill server node>
dhood@osrf-esteve:~/ros2_ardent [ros2_ardent]$ ros2 node list
<start it again>
dhood@osrf-esteve:~/ros2_ardent [ros2_ardent]$ ros2 node list
add_two_ints_server
<kill it again>
dhood@osrf-esteve:~/ros2_ardent [ros2_ardent]$ ros2 node list
dhood@osrf-esteve:~/ros2_ardent [ros2_ardent]$
built from source with connext on osx:
$ RMW_IMPLEMENTATION=rmw_connext_cpp ros2 node list
REDAWorker_enterExclusiveArea:worker U00007fff7a779300 deadlock risk: cannot enter 0x7fa690f9c770 of level 40 from level 40
REDACursor_modifyReadWriteArea:!enter worker (U00007fff7a779300)'s exclusive area
PRESPsService_removeRemoteEndpoint:!modify pres psRemoteWriter
REDAWorker_enterExclusiveArea:worker U00007fff7a779300 deadlock risk: cannot enter 0x7fa690f9c770 of level 40 from level 40
REDACursor_modifyReadWriteArea:!enter worker (U00007fff7a779300)'s exclusive area
PRESPsService_removeRemoteEndpoint:!modify pres psRemoteReader
add_two_ints_server
(no name)
(no name)
(no name)
(no name)
the (no name) output comes from this line in rmw_connext_cpp:
https://github.com/ros2/rmw_connext/blob/efaf513a5f9303216670ed76b5060ed5b8f958e5/rmw_connext_shared_cpp/src/node_names.cpp#L76
Perhaps this equivalent in fastrtps can return empty names: https://github.com/ros2/rmw_fastrtps/blob/3e5edb3316e2aee325e9354549e54c999a89bca9/rmw_fastrtps_cpp/src/rmw_node_names.cpp#L56
I haven't seen opensplice output empty lines.