Function

Poll current servers for application/topic name pairs that they are serving.

 

DDEPollTopics ( AppName_SV, Topic_SV )

 

•AppName_SV is a string value representing the server's DDE application name.  (If the server is an ESL program, it is the registered name.)

•Topic_SV is a string value representing the server's associated DDE topic name.  (If the server is an ESL program, it is the registered name.)

Description

Called by the client.  This function polls any currently running servers for the application/topic name pairs they are serving.

 

This function attempts to initiate conversations with all active servers, recording the application/topic pairs supplied by each responding server.  (See DDERegisterServer for the DDE protocol rules relating to how the server responds to client requests.)  Any conversation initiated as a result of this poll is immediately terminated.  Therefore, no permanent conversations are started as a result of this call.  You can examine the list that results from this poll by calling DDEEnumeratePollTopics along with DDEGetPollAppName and DDEGetPollTopic.  The return value is the number of entries in the list.

 

Poll topics do not accumulate across calls; each call to this function clears the previous list before the new entries are recorded.

Message

Broadcasts a WM_DDE_INITIATE message.

 

To prevent this function from stalling, it is possible to set a timeout option. To set the timeout, call the DDESetTimeOut routine.

Example

# Find all EASEL servers with "Easel" application name,

# and display their topics

 

copy 0 to LastTopic_IV

copy DDEPollTopics ("Easel", "") to NumConvs_IV

while (NumConvs_IV > 0) loop

   copy DDEEnumeratePollTopics (LastTopic_SV) to LastTopic_IV

   add to TopicWindow insert at cursor

      DDEGetPollTopic (LastTopic_IV) "\n"

   copy (NumConvs_IV - 1) to NumConvs_IV

end loop