Well, the compiler needs to know how the function printf() is to be used, and it can only find that information by looking at /usr/include/stdio.h (or wherever the system puts it). (A book on c would probably be helpful.) dan On Fri, Nov 6, 2009 at 11:10 AM, yacson <yactiem@xxxxxxxxx> wrote: > > Hi everybody. > Sorry, I'm a new user and i want to understand why this c code work (in > linux I'm worling on mandriva 2009 spring)? > main() > {printf("hello,world");} > > why does not the compiler complain about the missing stdio.h ? it just gives > "warning:incompatible implicit declaration of built-in function printf" and > actually prints the string "hello,world". > -- > View this message in context: http://old.nabble.com/sos-help-for-understanding-tp26230861p26230861.html > Sent from the gcc - Help mailing list archive at Nabble.com. > >