A conversation object.
A string or symbol.
A clipboard format specifier.
A keyword.
A boolean.
The function dde-request issues a request transaction on conversation for the specified item. The argument item should be a string, or a symbol. If it is a symbol its print name is used.
The argument format should be one of the following:
CF_ prefix), or the name of a registered clipboard format.:text. This is the default value.
The keyword :text is treated specially. If supported by the server it uses the CF_UNICODETEXT clipboard format, otherwise it used the CF_TEXT format.
The default conversation class only supports text formats, unless type is specified as :foreign. The argument type specifies how the response data should be converted to a Lisp object. For text formats, the default value indicates that a Lisp string should be created. The value :string-list may be specified for type to indicate that the return value should be taken as a tab-separated list of strings; in this case the Lisp return value is a list of strings. The value :foreign can be used with any clipboard format. It returns a clipboard-item structure, containing a foreign pointer to the data, the data length, and the format identifier.
This function returns two values, result and successp. If successful, result is the return value of the transaction (which may be nil in the case of :string-list), and successp is true to indicate success.
On failure, the result of the function depends on the errorp argument. If errorp is t (the default), the function signals an error. If errorp is nil, the function returns (values nil nil).
LispWorks User Guide and Reference Manual - 20 Sep 2017