Pathname identifying location of buffer.
An external format spec.
A buffer whose contents are examined.
Length (an integer) up to which buffer should be examined.
The result of reading the value returned from the
external-format option as a Lisp expression in the
external-format is found, it reads value as a Lisp expression in the
keyword package. If
coding is found, it attempts to translate value from a GNU Emacs coding system name to a LispWorks external-format name.
LispWorks User Guide and Reference Manual - 20 Sep 2017