This is some musing about the following set...
http://gmic.co.uk/index.php/topic/61459-french-commandantchef-de-bataillon/?p=578783
It is a commandant, traces and tailoring show he was originally in the 80th infantry Regiment... but seems to have transfered to the 2nd during the war.
- The 3 Stripes on the upper arm - two together, then a third added... seem to point to him having 18 months service when they were introduced in April 1916, and then getting two in one go.... then getting a third maybe in October 1916 for another 6 months.... but not being around for a fourth one which would have been due in April 1917.... so maybe wounded and no longer fit for service at the front...