list directory contents

-a     Write out all directory entries, including those whose names begin with a period ( '.' ).  Entries
       beginning  with  a  period shall not be written out unless explicitly referenced, the -a option is
       supplied, or an implementation-defined condition shall cause them to be written.

-l     (The  letter  ell.) Do not follow symbolic links named as operands unless the -H or -L options are
       specified. Write out in long format (see the STDOUT section). When -l (ell) is specified, -1 (one)
       shall be assumed.

-d     Do not follow symbolic links named as operands unless the -H or -L options are specified.  Do  not
       treat  directories  differently  than  other  types  of  files.  The  use  of  -d with -R produces
       unspecified results.

Commands separated  by  a ; are executed sequentially; the shell waits for each command to terminate in turn.  The
return status is the exit status of the last command executed.

execute a command as another user

change file mode bits

The  format  of  a  symbolic  mode  is  [ugoa...][[+-=][perms...]...], where perms is either zero or more
letters from the set rwxXst, or a single letter from the set ugo.  Multiple symbolic modes can be  given,
separated by commas.

Change the mode of each FILE to MODE.

list contents of directory

-l     List  in  long  format,  giving  mode (see below), file system type (e.g., for devices, the # code
       letter that names it; see intro(3)), the instance or  subdevice  number,  owner,  group,  size  in
       bytes, and time of last modification for each file.

-d     If argument is a directory, list it, not its contents.