Listing 10 A "Hello, world!" program

/* hello.c: Greet either the user or the world *\
#include <stdio.h>

main(int argc, char *argv[])
{
   if (argc > 1 && argv[1] != NULL)
      printf("Hello, %s!\n",argv[1]);
   else
      printf("Hello, world!\n");
   return 0;
}

/* End of File */