The logic is already written with the intent of failing silently if anacron is already running; that's what the "|| :" bit is for. Anacron can be started from multiple places (various cron entries and pm-utils), so it has to address the possibility of collisions from two instances starting at roughly the same time. (I'm only getting the e-mail infrequently, so this is what is probably happening in my case.)
If you find the e-mail messages useful for diagnosing hung jobs, then you'll need to file a separate feature request. For one, anacron would need better logic to determine when collisions are a result of those rather than two instances starting in close succession.
The logic is already written with the intent of failing silently if anacron is already running; that's what the "|| :" bit is for. Anacron can be started from multiple places (various cron entries and pm-utils), so it has to address the possibility of collisions from two instances starting at roughly the same time. (I'm only getting the e-mail infrequently, so this is what is probably happening in my case.)
If you find the e-mail messages useful for diagnosing hung jobs, then you'll need to file a separate feature request. For one, anacron would need better logic to determine when collisions are a result of those rather than two instances starting in close succession.