http://c-faq.com/null/machnon0.htmlCode:int main(void) { double f; memset(&f,0,sizeof(f)); printf("%f\n",f); char *p; memset(&p,0,sizeof(*p)); if(p == NULL) { printf("ok null\n"); } else { printf("nonoob is real noob\n"); } return 0; } 0.000000 nonoob is real noob
http://c-faq.com/~scs/cgi-bin/faqcat...=malloc#calloc