You can call C function by other language svery easily. But First you have to from which language you want to call C function.

You can call C function from JAVA by using features " JNI" of java.
detail : http://www.mactech.com/articles/mact...ava/index.html
http://www.java.sun.com/docs/books/t...tep/index.html

You can call C function from .net also by interop.
Detail you can see msdn . Code also there.