Removing ttf-opensymbol ...
Updating fontconfig cache...
/usr/share/fonts: failed to write cache
/usr/share/fonts/X11: failed to write cache
/usr/share/fonts/X11/100dpi: failed to write cache
/usr/share/fonts/X11/75dpi: failed to write cache
/usr/share/fonts/X11/Type1: failed to write cache
/usr/share/fonts/X11/encodings: failed to write cache
/usr/share/fonts/X11/encodings/large: failed to write cache
/usr/share/fonts/X11/misc: failed to write cache
/usr/share/fonts/X11/util: failed to write cache
/usr/X11R6/lib/X11/fonts: failed to write cache
/usr/X11R6/lib/X11/fonts/encodings: failed to write cache
/usr/X11R6/lib/X11/fonts/encodings/large: failed to write cache
/usr/local/share/fonts: failed to write cache
dpkg: error processing ttf-opensymbol (--purge):
 subprocess post-removal script returned error exit status 13
Errors were encountered while processing:
 ttf-opensymbol
E: Sub-process /usr/bin/dpkg returned an error code (1)
A package failed to install.  Trying to recover: