accessing c functions

Hi. I am working on a program for a class and was wondering if it would be possible, using view/pro, to: 1. send input to and execute a c function from rebol. 2. receive the output of the c function back to rebol. The reason I want to do this is because their is a recursive function in the code that needs to run fast.. is this possible? If so, what is the general way i would go about doing this? thanks, rishi

You certainly can. What you would do is compile a shared library with your C functions and then use the library component of View/Pro to access them. Check out the documentation on this component here: http://www.rebol.com/docs/library.html If you need more working examples, I'm sure the friendly folks on this list will help you out. Sterling

hmmm... thanks for the reply. I browsed through the doc but am a bit confused how to create a shared library. Has anyone done a simple program in rebol that calls a c function that takes input and returns something such as this: int add(int a, int b) {return(a+b);} A simple example of this would be useful (prefer windows example but unix is ok also)... any help would be appreciated... rishi --- [sterling--rebol--com] wrote:

Hi Rishi The rebol part of accessing a shared library (dll in Windows) is illustrated by a script on the Ecotope rebsite. The script shows how to access the functions in the C-Runtime library crtdll.dll on Win98. Just change the extension to .r. http://www.nwlink.com/~ecotope1/reb/clib.txt If you want to access some custom functions written in C, you will have to get a C programmer to write the code and compile it to a dll which exports those functions. They will be able to tell you the args and return specs for wrapping it in a Rebol routine. You need a View/Pro license or Command to access a shared library. HTH -Larry

hmmm...seems like my last message didn't get through. Anyway, thanks for the pointers. I guess i'll have to learn how to compile c code into shared libraries...Hopefully I won't have to read a whole book to do it... If it is too complicated, I wonder if it would be easier to write c functions and then use the rebol shell (instead of libraries) to send input and get output from the c functions (via the shell). I guess i'd have to convert the c output to a string and then in rebol, convert the string to valid rebol datatypes. on the flip side, I was also wondering, as crazy as it may sound, if it would be possible to put rebol code into a shared library so i can call it in my c code. The reason i'd like to do this is simply because in many of our programming assignments, we have to implement c functions within a larger program. I'd like to implement those functions in rebol by calling a shared rebol library...i doubt this is possible...but thought i'd ask anway.. rishi --- [sterling--rebol--com] wrote: