I have no experience with Boost.Log. But it seems the character "/" is reserved for the file system, thus not acceptable in file names. In you case, you are asking Boost,Log to creat 3 nested folders %Y, %m and %d, and then a file xxx_%N.log. Boost.Log may not support this as this function is supposed to be in Boost.Filesystem. HTH. 2011/4/29 <boost-request@lists.boost.org>

Date: Fri, 29 Apr 2011 18:43:35 +1000 From: Jinqiang Zhang <jasonzha@gmail.com> Subject: [boost] BoostLog: how to write log files into different folders named under Year/Month/Day

e.g. like "%Y/%m/%d/xxx_%N.log"

when I tried it, it created folder named %Y, ... but what I what is '2011' instead.

any idea ?

Jinqiang