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@@ -1,145 +0,0 @@
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-# 文件读写 #
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-
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-## 介绍 ##
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-
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-这个例程展示了如何进行文件读写。
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-
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-## 程序清单 ##
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-
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-```{.c}
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-/*
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- * 代码清单:文件读写例子
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- *
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- * 这个例子演示了如何读写一个文件,特别是写的时候应该如何操作。
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- */
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-
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-#include <rtthread.h>
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-#include <dfs_posix.h> /* 当需要使用文件操作时,需要包含这个头文件 */
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-
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-#define TEST_FN "/test.dat"
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-
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-/* 测试用的数据和缓冲 */
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-static char test_data[120], buffer[120];
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-
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-static void readwrite_sample(void)
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-{
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- int fd;
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- int index, length;
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-
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- /* 只写 & 创建 打开 */
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- fd = open(TEST_FN, O_WRONLY | O_CREAT | O_TRUNC, 0);
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- if (fd < 0)
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- {
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- rt_kprintf("open file for write failed\n");
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- return;
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- }
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-
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- /* 准备写入数据 */
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- for (index = 0; index < sizeof(test_data); index ++)
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- {
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- test_data[index] = index + 48;
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- }
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-
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- /* 写入数据 */
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- length = write(fd, test_data, sizeof(test_data));
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- if (length != sizeof(test_data))
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- {
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- rt_kprintf("write data failed\n");
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- close(fd);
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- return;
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- }
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-
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- /* 关闭文件 */
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- close(fd);
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-
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- /* 只写并在末尾添加打开 */
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- fd = open(TEST_FN, O_WRONLY | O_CREAT | O_APPEND, 0);
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- if (fd < 0)
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- {
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- rt_kprintf("open file for append write failed\n");
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- return;
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- }
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-
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- length = write(fd, test_data, sizeof(test_data));
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- if (length != sizeof(test_data))
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- {
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- rt_kprintf("append write data failed\n");
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- close(fd);
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- return;
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- }
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- /* 关闭文件 */
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- close(fd);
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-
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- /* 只读打开进行数据校验 */
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- fd = open(TEST_FN, O_RDONLY, 0);
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- if (fd < 0)
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- {
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- rt_kprintf("check: open file for read failed\n");
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- return;
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- }
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-
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- /* 读取数据(应该为第一次写入的数据) */
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- length = read(fd, buffer, sizeof(buffer));
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- if (length != sizeof(buffer))
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- {
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- rt_kprintf("check: read file failed\n");
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- close(fd);
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- return;
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- }
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-
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- /* 检查数据是否正确 */
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- for (index = 0; index < sizeof(test_data); index ++)
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- {
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- if (test_data[index] != buffer[index])
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- {
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- rt_kprintf("check: check data failed at %d\n", index);
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- close(fd);
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- return;
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- }
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- }
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-
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- /* 读取数据(应该为第二次写入的数据) */
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- length = read(fd, buffer, sizeof(buffer));
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- if (length != sizeof(buffer))
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- {
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- rt_kprintf("check: read file failed\n");
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- close(fd);
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- return;
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- }
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-
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- /* 检查数据是否正确 */
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- for (index = 0; index < sizeof(test_data); index ++)
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- {
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- if (test_data[index] != buffer[index])
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- {
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- rt_kprintf("check: check data failed at %d\n", index);
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- close(fd);
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- return;
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- }
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- }
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-
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- /* 检查数据完毕,关闭文件 */
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- close(fd);
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- /* 打印结果 */
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- rt_kprintf("read/write done.\n");
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-}
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-/* 导出到 msh 命令列表中 */
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-MSH_CMD_EXPORT(readwrite_sample, readwrite sample);
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-```
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-
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-## 运行结果 ##
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-
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-```
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-msh />readwrite_sample
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-read/write done.
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-msh />ls
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-Directory /:
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-dir_test <DIR>
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-text.txt 23
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-test.dat 240
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-msh />cat test.dat
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-0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\]^_`abcdefghijklmnopqrstuvwxyz{|}~ÇüéâäàåçêëèïîìÄÅÉæÆôöòûùÿÖÜ¢£¥₧ƒáíóúñѪº0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\]^_`abcdefghijklmnopqrstuvwxyz{|}~ÇüéâäàåçêëèïîìÄÅÉæÆôöòûùÿÖÜ¢£¥₧ƒáíóúñÑ
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-ªº
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-```
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-
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-运行示例代码后,可以看到程序分两次向 test.dat 文件中写入了 240 个字符的数据,第二次写入的数据追加在第一次写入的数据之后。
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