Well, the other day I was just thinking about how I keep getting bitten on code like this:

# Find all sub-dirs of $dir
opendir DIR, $dir or die "yaddah:$!";
@subdirs = grep { -d } readdir(DIR);
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This simple, obvious code doesn't do what I expect. The reason is that I keep forgetting to explictly do a chdir($dir): the "-d" is looking in the wrong place. So myself, I've been wondering why an "opendir" doesn't do a "chdir" for you... You can do the recursive equivalent of that task using File::Find like so:

use File::Find; 
find( sub { 
       -d && print $File::Find::name, "\n";
      }, 
      $dir );
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Without the implicit "chdir" behavior, you'd need to change the "-d" line to:

      -d $File::Find::name && print $File::Find::name, "\n";
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