[[inputs.system]] fails on SuSE with permission denied for utmp

[Crapworks]

Bug report

Relevant telegraf.conf:

[[inputs.system]]

System info:

Telegraf v1.5.2 (git: release-1.5 67440c9)
SuSE 11.3 (x86_64) (Kernel 3.0.93-0.8-xen)

Steps to reproduce:

1. Enable System Input Plugin
2. Run Telegraf

Expected behavior:

Gather metrics about load, uptime, etc.

Actual behavior:

Error:

Error in Plugin [inputs.system]: open /var/run/utmp: permission denied

Additional info:

ls -lha /var/run/utmp
-rw-r----- 1 root utmp 23K Feb 26 10:24 /var/run/utmp

Proposal:

It seems that this error is coming from the gopsutil library. It would be nice to be able to disable that specific feature to avoid reading utmp, or if reading it fails, still gather the metrics that are note dependent on that file being readable.

I am aware that I can also add the Telegraf user to the utmp group, but I would rather have this work out of the box.