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 restriction that the user must be the owner of the special file. This may be useful
       e.g. for /dev/fd if a login script makes the console user  owner  of  this  device.
       The  group  option is similar, with the restriction that the user must be member of
       the group of the special file.
 
       The programs mount and umount maintain a list of currently mounted file systems  in
       the file /etc/mtab.  If no arguments are given to mount, this list is printed.
 
       When  the  proc  filesystem  is  mounted  (say  at  /proc), the files /etc/mtab and
       /proc/mounts have very similar contents. The former has somewhat more  information,
       such  as  the  mount  options  used,  but is not necessarily up-to-date (cf. the -n
       option below).  It  is  possible  to  replace  /etc/mtab  by  a  symbolic  link  to
       /proc/mounts, and especially when you have very large numbers of mounts things will
       be much faster with that symlink, but some information is lost  that  way,  and  in
       particular  working  with  the  loop  device will be less convenient, and using the
       "user" option will fail.