command [ -pvV ] simple command
       The simple command argument is  taken  as  an  external  command
       instead  of  a  function  or  builtin  and  is  executed. If the
       POSIX_BUILTINS option is set, builtins will also be executed but
       certain  special  properties of them are suppressed. The -p flag
       causes a default path to be searched instead of that  in  $path.
       With  the  -v flag, command is similar to whence and with -V, it
       is equivalent to whence -v.

       See also the section `Precommand Modifiers'.
