/*Calling external functions in C (from externalfunc.c) */
/* also see Makeextern - use command make -f Makeextern */
/* to compile without make:
gcc -c externalfunc.c
gcc -o extern externalfunc.o
The first line produces externalfunc.o, the second compiles
external.c and links it to externalfunc.o */

#include <stdio.h>
#include <string.h>
#include "externalfunc.h" /*contains extern statement */

int main (void)
{
  world();
}