setting log4j file path

[Jeff]

Is there some mechanism in log4j to have it guess the file path separator or
force it depending on the OS?

My app runs on Windows or Unix. For application files, I use Java's file
separator specification to swap between \usr\local\myApp and
C:/Programs/myApp . Is there a similar mechanism in log4j? Should I just
create log4j configurations for each OS?

Thanks