title: Does any Unix-like system ascribe meaning to the SUID bit on a directory?
body: <p>As the title says, does any Unix-like system ascribe a meaning to the SUID bit on a <strong>directory</strong>, and if so, what does it mean?</p>
  
  <p>The SVTX (saved text, or sticky) bit has a meaning - thou shalt not delete a file from this directory unless you can write to the file.  It is used on /tmp, for example.</p>
  
  <p>The SGID (set GID) bit has a meaning - files created in this directory shall belong to the group that owns the directory (though that assignment can later be changed by an explicit call to chown(2)).</p>
  
  <p>What about the SUID bit?</p>