#include <stdlib.h>#include <stdio.h>#include <sys/stat.h>#include <sys/mman.h>#include <string.h>#ifndef	MAP_NORESERVE#define	MAP_NORESERVE	0#endifvolatile char ch;main(){    struct stat statbuf;    uchar *buf;    fstat(0, &statbuf);    buf = mmap(NULL, statbuf.st_size, PROT_READ, MAP_SHARED|MAP_NORESERVE,	0, 0);    if(buf != (uchar*)(-1)){	uchar *cur, *lim = &buf[statbuf.st_size];	for(cur = buf; buf != lim; ++cur){	    ch = *cur;	}	munmap(buf, statbuf.st_size);    }}