Description of problem:

With some image displayed most of any actions on "Miscellany" menu
brings alerts like:

   Unable to show histogram /tmp/magick-XXVkjgrM

It is not that surprising as a quick examination reveals that
any of /tmp/magick-* files is actually empty.  Still after showing
this alert ImageMagick goes and performs a requested action anyway;
clearly on some other file.

Regardless, actions sometimes have strange side-effects.  For example
"Preview" of a PNG file once painted gray the whole gnome-terminal
window from which 'display' was started and, after a short while,
killed all gnome-terminal windows around; even those which were
started as separate processes.  This I cannot reproduce.

Version-Release number of selected component (if applicable):
ImageMagick-6.0.7.1-4

How reproducible:
100% ("unable" alerts)