here is the very simple bob.c:

main()
{
printf("hello");
}

i use tiger and i use the command:
gcc bob.c

and the end result:

bob.c: In function ‘main’:
bob.c:3: warning: incompatible implicit declaration of built-in function /‘printf’


any help appreciated, i'm just starting up, hopefully thanks in advance

add the header file stdio.h in the beginning of the program :
#include <stdio.h>

that got rid of the errors, but now the printf() function does not output

Do you mean the OS X Tiger...state the platform you are compiling on? What header files are you including besides <stdio.h> and what libs are you compiling with? There might be issues with the printf() definition between the header files and libs you are compiling with.

i downloaded xcode thats it