How can I call a dll form another dll written in cpp without it crashing on me

[TheShaps]

Hello guys!
I am new to the forum, I have a question which I posted on:
http://stackoverflow.com/questions/31514335/how-can-i-call-a-dll-form-another-dll-written-in-cpp-without-it-crashing-on-me
Everything is there.
*Moderators, I am new to this forum so I don't know the rules, so if you feel like I need to post the same thing on this forum please let me know, and don't lock this thread.
Other wise please feel comfortable answering where ever you like.
Thanks guys

[Computergeek01]

If your application is crashing mid way through execution then you are definitely getting a runtime error; what does that error say? (Control Panel -> Administrative Tools -> Event Viewer: Application section). Please include that in your next post.

I don't know what "DllCall()" is from, are you certain that it is a variadic function?

Usually crashes like this occur because the function that the application was expecting to be avalible at runtime is not loaded into memory. There are a few things that you could try, the first one I would suggest is inserting a break point just before the suspected call and enumerating the DLL files that are loaded with either SysInternals 'Procmon' or the command line tool 'tasklist' like this:

tasklist /m /fi "imagename eq <PROCESS_NAME>"

with not triangle brackets of course.

[TheShaps]

Thanks for answering , I tried the Event Vierwer thing, but once I opened it, I couldn't find my processes, which is called DLLCall.au3 (which is an Autoit script that calls the dll) of course when the proccess was running.
I also tried the command you game me but this is what happned:
C:\Users\Nyname>tasklist /m /fi "imagename eq DLLCall.au3"
INFO: No tasks are running which match the specified criteria.

DllCall() is a function in Autoit that calls a dll, as mention in the original post. I now for a fact that the imgsearch.dll is loaded to memory properly because I get a msgbox

  hinstLib = LoadLibrary(TEXT("D:\\Downloads\\SmartGuy\\SmartGuy\\imgs\\imgsearch.dll")); 
 
    // If the handle is valid, try to get the function address.
 
    if (hinstLib != NULL) 
    { 
		std::cout << "DLL Called! Hello AutoIt!" << std::endl; // This silly function will just output in our Autoit script "Dll Called!"
      MessageBox(0, TEXT("hinstLib != NULL"), TEXT("Simple Dll..."),0);  //  

thanks

[Computergeek01]

When you actually go to call the function, are you remembering to initialize the void pointer 'HBMP' so that it points to a space that was intentionally allocated for it with something like "memset(...)" "malloc()"? I only ask because you admit to being a 'noob' as you put it.

[TheShaps]

yea I just double checked and HBMP has a valid value.

[Computergeek01]

And the buffer is large enough to contain the object populated by "ImageSearchEx()", right? 'void' pointers suck because they don't tell you anything.