pushd [ -qsLP ] [ arg ]
pushd [ -qsLP ] old new
pushd [ -qsLP ] {+|-}n
       Change the current directory, and push the old current  directory
       onto  the directory stack.  In the first form, change the current
       directory to arg.  If arg is not specified, change to the  second
       directory  on  the stack (that is, exchange the top two entries),
       or change to $HOME if the PUSHD_TO_HOME option is set or if there
       is only one entry on the stack.  Otherwise, arg is interpreted as
       it would be by cd.  The meaning of old and new in the second form
       is also the same as for cd.

       The third form of pushd changes directory by rotating the  direc-
       tory list.  An argument of the form `+n' identifies a stack entry
       by  counting from the left of the list shown by the dirs command,
       starting with zero.  An argument of the form `-n' counts from the
       right.  If the PUSHD_MINUS option is set, the meanings of `+' and
       `-' in this context are swapped.

       If the -q (quiet) option is specified, the  hook  function  chpwd
       and  the  functions in the array $chpwd_functions are not called,
       and the new directory stack is not printed.  This is  useful  for
       calls  to pushd that do not change the environment seen by an in-
       teractive user.

       If  the  option  -q  is  not  specified  and  the  shell   option
       PUSHD_SILENT  is not set, the directory stack will be printed af-
       ter a pushd is performed.

       The options -s, -L and -P have the same meanings as  for  the  cd
       builtin.