Thread: LNK2019: unresolved external symbol

I built an MFC GUI and am now trying to tie in a networking API. With the api came come console based examples, which are pretty straightforward. But, I’m trying to add the trader class to my application I added the .h file and everything went fine. Then I’m started to include the class functions 1 by 1… I’m only doing the constructor right now and I start to get all these error LNK2019: unresolved external symbol in the Basic_Order_WindowDLG.obj
(the application is just a dialog box) What am I doing wrong?

Never mind the above question I realized I didn't include some libs into my project settings... after that it was fine. I do still have 1 more question though.

I'm implementing a networking class into a MFC application, this class was written originally for a console application, so there are printf’s ect throughout it. It’s builds but I’m wondering what effect these will have on the MFC application since it’s not console based?

printf will do nothing if there is no console. It wont crash your program or anything though.

If you want output to the "console" esp while in a MS compiler, I suggest you check out the TRACE line of macros, in case you wanted the output that would be the way. But if you don't care then bithub is right printf shouldn't do anything nasty at all.