diff -r bd25d9f9d9dc -r 34775227c84f hws/hw04.tex
--- a/hws/hw04.tex	Sat Sep 23 14:19:09 2017 +0100
+++ b/hws/hw04.tex	Sat Sep 23 19:32:21 2017 +0100
@@ -54,44 +54,6 @@
   general, but in particular for root, to have \texttt{.} as the first
   entry in ones variable \texttt{PATH}?
 
-\item A Unix directory might look as follows:
-
-\begin{center}
-\begin{verbatim}
-$ ls -ld . * */*
-drwxr-xr-x 1 ping staff  32768 Apr  2 2010 .
--rw----r-- 1 ping students  31359 Jul 24 2011 manual.txt
--r--rw--w- 1 bob students   4359 Jul 24 2011 report.txt
--rwsr--r-x 1 bob students 141359 Jun  1 2013 microedit
-dr--r-xr-x 1 bob staff  32768 Jul 23 2011 src
--rw-r--r-- 1 bob staff  81359 Feb 28 2012 src/code.c
--r--rw---- 1 emma students    959 Jan 23 2012 src/code.h
-\end{verbatim}
-\end{center}
-
-with group memberships assigned as follows:
-\begin{center}
-\begin{tabular}{ll}
-Members of group staff: & ping, bob, emma\\ 
-Members of group students: & emma\\
-\end{tabular}
-\end{center}
-
-The file microedit is a text editor, which allows its users to open, edit and 
-save files. Note carefully that microedit has set its setuid flag. 
-Fill in the access control matrix below that shows for each of the above five files, 
-whether ping, bob, or emma are able to obtain the right to read (R) or replace (W) its 
-contents using the editor microedit.\bigskip
-
-\begin{center}
-\begin{tabular}{r|c|c|c|c|c}
-        & manual.txt & report.txt & microedit & src/code.c & src/code.h \\\hline
-ping & & & & &\\\hline
-bob & & & & &\\\hline
-emma   & & & & &\\
-\end{tabular}
-\end{center}
-
 \item In the context of which information flow should be protected, explain briefly the 
 differences between the {\it read rule} of the Bell-LaPadula access
 policy and the Biba access policy. Do the same for the {\it write rule}.