rt-thread/examples/file/readwrite.c

/*
 * File      : readwrite.c
 * This file is part of RT-TestCase in RT-Thread RTOS
 * COPYRIGHT (C) 2010, RT-Thread Development Team
 *
 * The license and distribution terms for this file may be
 * found in the file LICENSE in this distribution or at
 * http://www.rt-thread.org/license/LICENSE
 *
 * Change Logs:
 * Date           Author       Notes
 * 2010-02-10     Bernard      first version
 */
#include <rtthread.h>
#include <dfs_posix.h>

#define TEST_FN		"/test.dat"

static char test_data[120], buffer[120];

/* <20>ļ<EFBFBD><C4BC><EFBFBD>д<EFBFBD><D0B4><EFBFBD><EFBFBD> */
void readwrite(const char* filename)
{
	int fd;
	int index, length;

	/* ֻд & <20><><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD> */
	fd = open(TEST_FN, O_WRONLY | O_CREAT | O_TRUNC, 0);
	if (fd < 0)
	{
		rt_kprintf("open file for write failed\n");
		return;
	}

	/* ׼<><D7BC>д<EFBFBD><D0B4><EFBFBD><EFBFBD><EFBFBD><EFBFBD> */
	for (index = 0; index < sizeof(test_data); index ++)
	{
		test_data[index] = index + 27;
	}

	/* д<><D0B4><EFBFBD><EFBFBD><EFBFBD><EFBFBD> */
	length = write(fd, test_data, sizeof(test_data));
	if (length != sizeof(test_data))
	{
		rt_kprintf("write data failed\n");
		close(fd);
		return;
	}

	/* <20>ر<EFBFBD><D8B1>ļ<EFBFBD> */
	close(fd);

	/* ֻд<D6BB><D0B4><EFBFBD><EFBFBD>ĩβ<C4A9><CEB2><EFBFBD>Ӵ<EFBFBD><D3B4><EFBFBD> */
	fd = open(TEST_FN, O_WRONLY | O_CREAT | O_APPEND, 0);
	if (fd < 0)
	{
		rt_kprintf("open file for append write failed\n");
		return;
	}

	length = write(fd, test_data, sizeof(test_data));
	if (length != sizeof(test_data))
	{
		rt_kprintf("append write data failed\n");
		close(fd);
		return;
	}
	/* <20>ر<EFBFBD><D8B1>ļ<EFBFBD> */
	close(fd);

	/* ֻ<><D6BB><EFBFBD>򿪽<EFBFBD><F2BFAABD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>У<EFBFBD><D0A3> */
	fd = open(TEST_FN, O_RDONLY, 0);
	if (fd < 0)
	{
		rt_kprintf("check: open file for read failed\n");
		return;
	}

	length = read(fd, buffer, sizeof(buffer));
	if (length != sizeof(buffer))
	{
		rt_kprintf("check: read file failed\n");
		close(fd);
		return;
	}
	for (index = 0; index < sizeof(test_data); index ++)
	{
		if (test_data[index] != buffer[index])
		{
			rt_kprintf("check: check data failed at %d\n", index);
			close(fd);
			return;
		}
	}

	length = read(fd, buffer, sizeof(buffer));
	if (length != sizeof(buffer))
	{
		rt_kprintf("check: read file failed\n");
		close(fd);
		return;
	}
	for (index = 0; index < sizeof(test_data); index ++)
	{
		if (test_data[index] != buffer[index])
		{
			rt_kprintf("check: check data failed at %d\n", index);
			close(fd);
			return;
		}
	}
	/* <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ϣ<EFBFBD><CFA3>ر<EFBFBD><D8B1>ļ<EFBFBD> */
	close(fd);
	/* <20><>ӡ<EFBFBD><D3A1><EFBFBD><EFBFBD> */
	rt_kprintf("read/write done.\n");
}

#ifdef RT_USING_FINSH
#include <finsh.h>
FINSH_FUNCTION_EXPORT(readwrite, perform file read and write test);
#endif