Hope i'm in the correct group here... sorry if i'm not

I wrote a small section of code recently which i saved in a file called
shell.cpp.  Nothing spectacular, but when run it refused to produce any output.
I cut the program back to nothing except a
void main(void)
{
 printf("hello");
}
and it still didn't do squat!

Only when i renamed the file to test.cpp did it work.  Bug or wot?  The filename
should not effect the program.

Fantom