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:
A DDE format specifier, consisting of either a standard clipboard format or a registered clipboard format.
A string containing either the name of a standard clipboard format (without the CF_ prefix), or the name of a registered clipboard format.
A symbol, in which case its print name is taken to specify the clipboard format.
The keyword :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) .