Osmosis/keep a local copy of a .osm file updated using minutely updates

First get tendring.osm by downloading a Geofabrik extract in non-pbf format, and extracting it using

osmosis --rx essex.osm.gz2 --bp clipIncompleteEntities=yes file=tendring.txt --wx tendring.osm

The tendring.txt bounding polygon is available from the Tendring(Essex District) page.

Once only execute

osmosis --rrii 

to prepare for synchronisation.

Edit configuration.txt if you want to download more than 3600 seconds worth of updates at a time, or want to use hourly diffs rather than minutely.

Download a state.txt file from planet.openstreetmap.org - pick a nnn.state.txt earlier than the Geofabrik extract timestamp (I chose 23:59 of previous day) and save in same folder as configuration.txt as state.txt

Then run

osmosis --rri --simc --rx tendring.osm --ac --bp clipIncompleteEntities=yes file=tendring.txt --wx new.osm 
   && copy new.osm tendring.osm /y && del new.osm

as often as it takes to catch up. The above is for Windows 7. Linux seems to have a mv command which will replace the copy and del commands.