The DDE Extension

   

Practical Programming in Tcl & Tk, Third Edition
By Brent B. Welch

Table of Contents
Chapter 52.  Tcl/Tk 8.1


DDE (Dynamic Data Exchange) is a communication protocol used among Windows applications. The protocol exchanges data with a server identified by name. Each service implements a number of operations known as topics. The data exchange can be synchronous or asynchronous. The dde command is implemented as an extention that is distributed with Tcl. You must use package require dde to load the extension. The dde command is summarized in Table 52-2

Table 52-2. The dde command options.
dde servername ?topic?Registers the current process as a DDE service with name TclEval and the given topic. If topic is not specified, this command returns the currently registered topic.
dde ?-async? execute service topic dataSends data to the service with the given topic.
dde ?-async? eval topic cmd ?arg ...?Sends cmd and its arguments to the TclEval service with the given topic. This is an alternative to the Tk send command.
dde ?-async? poke service topic dataSimilar to the execute operation, but some services export operations under poke instead of execute.
dde ?-async? request service topic itemFetches the named item from the service with the given topic.
dde services server topicReturns server and topic if that server currently exists, otherwise it returns the empty string.
dde services server {}Returns all the topics implemented by server.
dde services {}topicReturns all servers that implement topic.
dde services {} {}Returns all server, topic registrations.


       
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    Practical Programming in Tcl and Tk
    Practical Programming in Tcl and Tk (4th Edition)
    ISBN: 0130385603
    EAN: 2147483647
    Year: 1999
    Pages: 478

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