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dde-advise-start Function


Sets up an advise loop on a specified data item for a conversation.




dde-advise-start conversation item &key key function format datap type errorp => result

A conversation object.
A string or symbol.
An object.
A function name.
A clipboard format specifier.
A boolean.
A keyword.
A boolean.
A boolean.

The function dde-advise-start sets up an advise loop for the data item specified by item on the specified conversation.

See 22.2.3 Advise loops for information about DDE advise loops.

format should be one of the following:

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 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 default conversation class only supports text formats, unless type is specified as :foreign, which 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.

If datap is t (the default value), a hot link is established, where the new data is supplied whenever it changes. If datap is nil, a warm link is established, where the data is not passed, and must be explicitly requested using dde-request.

key is used to identify this link. If specified as nil (the default value), it defaults to the conversation. Multiple links are permitted on a conversation with the same item and format values, as long as their key values differ.

If the link is established, the return value result is t. If the link could not be established, the behavior depends on the value of errorp. If errorp is t (the default value), LispWorks signals an error. If it is nil, the function returns nil to indicate failure.

If the link is established, the function function is called whenever the data changes. If function is nil (the default value), then the generic function dde-client-advise-data will be called.

The function specified by function should have a lambda list similar to the following:

key item data &key conversation &allow-other-keys

key and item identify the link. data contains the new data for hot links; for warm links it is nil.

See also


LispWorks® User Guide and Reference Manual - 01 Dec 2021 19:31:09