Hello experts,

I have been writing a SC frontend for a powersupply. I have used the model 
where the frontend can be started with "-i n" option so that each fe can 
control a different supply. During the development/testing of the program I 
would normally only run a single instance with "-i 1". However when I started
a second instance with "-i 2" I found problems with the history plots that
were being made for the original "-i 1" instance. The variable being plotted
seemed to randomly jump between the value from the "-i 1" instance and 
the "-i 2" instance.  confirmed that the "correct" values exist for each 
frontend in the odb under /Equipment/Foo01/Variables and 
/Equipment/Foo02/Variables

This is also not just a plotting artifact since I was also
able to see the two different values by running mhist.

I saw this behaviour using midas-2019-03 and also the head of the development
branch (686e4de2b55023b0d1936c60bcf4767c5e6caac0 from just under 48 hours ago). 

I was able to reproduce this with a stripped down frontend that just 
sets a variable that is equal to its frontend_index. Please find the code 
and Makefile attached. Presumably I've done something wrong in my 
implementation that hopefully a more experienced person can spot quite 
quickly, but please let me know if any more information is needed.

I have seen this behaviour on both Debian 10 and on a CentOS 7 Singularity 
image running on top of Debian 10.

Thanks,

Nick.

P.S. I made the topic of this post "Forum" and not "Bug Report" since I
expect the root of this problem is somewhere between the keyboard and chair.