dan@dbdb$ ls -l somefile.png
-r-------- 1 dboger 3813 2008-06-05 16:46 somefile.png

##</code><code>##

dan@dbdb$ perl -le 'print "lies" if -r shift' somefile.png
dan@dbdb$

##</code><code>##

dan@dbdb$ sudo perl -le 'print "lies" if -r shift' somefile.png
lies
dan@dbdb$ sudo file somefile.png
couldn't open file
somefile.png: regular file, no read permission