这里用的f_write是例程中自带的,应该没有错吧。可是不知道为什么就是写不进去。
例如试验如下:
A.txt原有内容是zyz
在超级终端输入命令:
write a.txt china
显示是写成功的,可是打开a.txt。里面的内容却不是china,而是原来的数据。哪位前辈帮帮忙忙看看?
int
Cmd_write(int argc, char *argv[])
{
FRESULT fresult;
unsigned short usBytesWrite=0;
if(strlen(g_cCwdBuf) + strlen(argv[1]) + 1 + 1 > sizeof(g_cTmpBuf))
{
UARTprintf("Resulting path name is too long
");
return(0);
}
//这一句的作用是判定将要写的文件添加到当前工作路径后,路径长度会不会超过缓冲区大小。
strcpy(g_cTmpBuf, g_cCwdBuf);
//将当前路径拷贝到缓冲区。
if(strcmp("/", g_cCwdBuf))
{
strcat(g_cTmpBuf, "/");
}
//在路径后面加上一个 / 分隔符
strcat(g_cTmpBuf, argv[1]);
//将要写的文件名添加到当前工作路径后面
fresult = f_open(&g_sFileObject, g_cTmpBuf, FA_WRITE);
//打开文件,用来写。
if(fresult != FR_OK)
{ UARTprintf("open error
");
return(fresult);
}
//如果打开过程中有错,就返回一个错误。
strcpy(g_cTmpBuf, argv[2]);
//将要写的内容拷贝到缓冲区
do
{
fresult = f_write(&g_sFileObject,g_cTmpBuf,sizeof(g_cTmpBuf) - 1,
&usBytesWrite);
//写文件
if(fresult != FR_OK)
{
UARTprintf("write error
");
return(fresult);
}
//
// Null terminate the last block that was read to make it a
// null terminated string that can be used with printf.
//
}while(usBytesWrite!=sizeof(g_cTmpBuf) - 1);
//循环写入,直到写完。
//
// Print the last chunk of the file that was received.
//
UARTprintf("%s", g_cTmpBuf);
//
// Continue reading until less than the full number of bytes are
// read. That means the end of the buffer was reached/
//
// Return success.
//
return(0);
}
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