Where is gazebo logging the msgs?

edit

When I do:

~$ roslaunch gazebo_ros empty_world.launch

my gazebo fails with a msg like:

[gazebo-1] process has died [pid 14193, exit code 255, cmd /opt/ros/kinetic/lib/gazebo_ros/gzserver -e ode worlds/empty.world __name:=gazebo __log:=/home/rosclient/.ros/log/fbf9970c-13c4-11e7-af34-080027063d61/gazebo-1.log]. log file: /home/rosclient/.ros/log/fbf9970c-13c4-11e7-af34-080027063d61/gazebo-1*.log

then I move to that path but there is no such a log file there from gazebo...

where is then?

thanks