How to call C functions in ASP

allang · June 8th, 2003, 09:26 PM

Hi,
Does anyone know how to call C excutables within asp pages?

Thanks

David Cameron · June 9th, 2003, 07:18 PM

Do you want to call a function or an executable?

To call a C function from within an asp page means that the C code must be compiled into a COM object and that the function must be exposed. I wrote some code that did this once using VC++ 6 and it was a major headache. Either you know the inner workings of COM well, or you let the compiler generate all the code for you (and be prepared to start from the beginning each time you make a nmistake).

To a C execuable is a different kettle of fish. In fact it is just an executable. You can create a WScript object, which basically gives you access to the command line and you can execute any executable from there. I'm not sure about capturing the output, but you would certainly be able to read a text file.

Let me know which of these you want and I can provide more information.

regards
David Cameron

allang · June 9th, 2003, 08:18 PM

Hi David,
thanks for the info.
Sorry about the confusion, I am actually trying to use a C executable in asp.
So if you have any more info in that area, please let me konw.
Also, I'm not too familiar with the WScript and how to go about to create one.
It'd be great if u can provide some sample code or detailed description.

Thanks Again

Allan

David Cameron · June 9th, 2003, 08:24 PM

Code:

Dim wssShell
Dim intRet

Set wshShell = Server.CreateObject("WScript.Shell")

intRet = wshShell.Run("executable goes here", 6, True)

Set wshShell = Nothing

intRet holds the return value from the application (In C normally 0 of everything was OK). I don't know about capturing the printf()/std::cout text.

regards
David Cameron

pgtips · June 10th, 2003, 06:42 AM

If you need to capture stdout then, presumably, you have a C command-line program so you should use the Exec method of the WScript.Shell object, not the Run method. The Exec method returns an object which has properties/methods for capturing stdout.