freeze.c

来自「<B>Digital的Unix操作系统VAX 4.2源码</B>」· C语言 代码 · 共 37 行

#ifndef lint
static	char	*sccsid = "@(#)freeze.c	4.1	(ULTRIX)	7/17/90";
#endif

#include "stdio.h"
freeze(s) char *s;
{	int fd;
	unsigned int *len;
	len = (unsigned int *)sbrk(0);
	if((fd = creat(s, 0666)) < 0) {
		perror(s);
		return(1);
	}
	write(fd, &len, sizeof(len));
	write(fd, (char *)0, len);
	close(fd);
	return(0);
}

thaw(s) char *s;
{	int fd;
	unsigned int *len;
	if(*s == 0) {
		fprintf(stderr, "empty restore file\n");
		return(1);
	}
	if((fd = open(s, 0)) < 0) {
		perror(s);
		return(1);
	}
	read(fd, &len, sizeof(len));
	/* (void) */  brk(len);
	read(fd, (char *)0, len);
	close(fd);
	return(0);
}