freebsd-src/lib/libdisk/blocks.c
1997-02-22 15:12:41 +00:00

42 lines
979 B
C

/*
* ----------------------------------------------------------------------------
* "THE BEER-WARE LICENSE" (Revision 42):
* <phk@login.dknet.dk> wrote this file. As long as you retain this notice you
* can do whatever you want with this stuff. If we meet some day, and you think
* this stuff is worth it, you can buy me a beer in return. Poul-Henning Kamp
* ----------------------------------------------------------------------------
*
* $Id$
*
*/
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <err.h>
#include "libdisk.h"
void *
read_block(int fd, daddr_t block)
{
void *foo;
foo = malloc(512);
if (!foo)
err(1,"malloc");
if (-1 == lseek(fd, (off_t)block * 512, SEEK_SET))
err(1, "lseek");
if (512 != read(fd,foo, 512))
err(1,"read");
return foo;
}
void
write_block(int fd, daddr_t block, void *foo)
{
if (-1 == lseek(fd, (off_t)block * 512, SEEK_SET))
err(1, "lseek");
if (512 != write(fd,foo, 512))
err(1,"write");
}