How to create a FWHM file with glim_image?

Does anybody know how to create a FWHM file with glim_image? I have noticed that there are some options that look interesting (e.g.-fwhm_gauss), but I seem to be facing syntax problems. It would be great if anybody could provide me with an example command line.

Given that no-one else seems to have had a crack at this my guess is that you are after something with which you can evaluate your mean fit?
In this case I’m guessing you want this:
glim_image \
-t_stat stats.mnc t_stat voxel column 2 \
-fwhm \
-fwhm_avg fwhm.mnc \
Note that I have not tested the above but from dim-dark memory this seems to ring a bell.