Comment 1 for bug 1480892

[SRU Justification] (Vivid, Trusty)

Thermald lockfile has been broken during a code cleanup, meaning multiple instances of thermald can be started. This fix is required to re-instate the lockfile functionality while also performing correct closure and removal of the lock file on thermald termination (be it an error or a successful termination). Thus this fix restores the original functionality plus it also cleans up the lockfile too.

[Test Case]
Without the fix, one can start multiple instances of thermald, e.g run the following while thermald is running as a service:

sudo thermald --no-daemon --loglevel=info

With the fix, thermald will detect another instance of thermald (via the lockfile) and terminate with an error message, for example:

Couldn't get lock file 21449
An instance of thermald is already running, exiting ...

[Regression Potential]
Can't think of any.