DTN IQFeed, DTN.IQ, DTN ProphetX Support Forums

Join the 80,000 other DTN customers who enjoy the fastest, most reliable data available. There is no better value than DTN!

(Move your cursor to this area to pause scrolling)

"Just a quick one to say I'm very impressed so far :) The documentation for developers is excellent and I've quickly managed to get an app written to do historical downloads. The system is very robust and pretty quick considering the extent of data that's available. The support guys have been very helpful too, in combination with the forums it's been plain sailing so far!" - Comment from Adam

"I had always used ******* but for the past 2 weeks have been trying DTN IQFeed. Customer support has been extraordinary. They call just to make sure your problem hasn't recurred." - Comment from Public Forum

"Very impressed with the quality of your feed - ******* is a real donkey in comparison." - Comment from A.C. via Email

"If you are serious about your trading I would not rely on IB data for serious daytrading. Took me a while to justify the cost of IQ Feed and in the end, it's just a 2 point stop on ES. Better safe than sorry" - Comment from Public Forum

"I was on the phone with a friend who uses CQG and right after the Fed announcement, CQG was as much as 30 seconds behind DTN.IQ. Some quotes were off by as much as 15-18 cents. Your feed never missed a beat." - Comment from Roger

"It’s so nice to be working with real professionals!" - Comment from Len

"Everything is working great with the API. I love it." - Comment from Calvin

"If someone needs the best quality data and backfill beyond what their broker provides at a rate that is the best in the industry, I highly recommend IQFeed." - Comment from Josh via Public Forum

"Boy, probably spent a thousand hours trying to get ******* API to work right. And now two hours to have something running with IQFeed. Hmmm, guess I was pretty stupid to fight rather than switch all this time. And have gotten more customer service from you guys already than total from them… in five years." - Comment from Jim

"This is an excellent value, the system is generous (allowing for 500 stocks) and stable (and really is tick-by-tick), and the support is fantastic." - Comment from Shirin via Email

Home

Recent Posts

Information on DTN's Industries:
DTN Oil & Gas | DTN Trading | DTN Agriculture | DTN Weather

DTN.IQ/IQFeed on Twitter
DTN News and Analysis on Twitter

»Forums Index »Archive (2017 and earlier) »IQFeed 3rd Party Software Support »IQFeed Client and IPWorks - Free Heap Block Error

Author	Topic: IQFeed Client and IPWorks - Free Heap Block Error (3 messages, Page 1 of 1)
peterjslater -Interested User- Posts: 2 Joined: May 8, 2012	Posted: May 8, 2012 01:45 AM Msg. 1 of 3 Hi I am a 3rd party developer using ipworks (http://www.nsoftware.com/ipworks/) TCP/IP Delphi component to connect to IQFeed 4.8 ( using sockets on localhost (127.0.0.1) I am making a request for history to the IQFeed client (HD,... ) and once the history is received, I disconnect the socket and free the socket connection. PROBLEM: After I free the socket (IPWorks Socket) in our program, IQFeed outputs the following in the outputdebug log. HEAP[???.exe] HEAP: Free Heap block 1da81da0 modified at 1da81e2c after it was freed Ignoring Non-user Breakpoint at $76FD04E5. If I do not free the socket (and cause a memory leak) the error does not occur. It appears that IQFeed is modifying some memory after its been free'd. Any thoughts ? p.s. When this error occurs we sometime get random memory problems in the program as the memory that is over written is sometimes being used by something else.
DTN_Steve_S -DTN Guru- Posts: 2093 Joined: Nov 21, 2005	Posted: May 11, 2012 01:44 PM Msg. 2 of 3 Sorry for the delay responding but this is not likely to be anything in IQConnect itself (although if it is, it is certainly something we would like to track down). What is outputting the debug log? Other than the fact that it happens when you shut down your end of the socket, do you have anything that points to this actually being something in IQConnect as opposed to the socket control you are using?
peterjslater -Interested User- Posts: 2 Joined: May 8, 2012	Posted: May 14, 2012 12:57 AM Msg. 3 of 3 I am note sure what is generating the outputdebug, I thought it might be the iqfeed client actually. I have not had this problem with the socket control for other projects.