我正在尝试从.dat文件读取结构...
要读取的第一个整数是读数的数量
然后有以下结构格式的数据

struct Oven
{
int rec_no;
int temp;
int status;
char string[10];
};


下面是我读取文件的方法

int read_and_process_file()
{
    int counter;
    FILE *ptr_myfile;
    struct Oven my_record;

    ptr_myfile=fopen("data.dat","rt");

    //for no of readings
    fread(&no_of_readings,sizeof(no_of_readings),1,ptr_myfile);


        for ( counter=1; counter <= 50; counter++)
        {
              fread(&my_record,sizeof(struct Oven),1,ptr_myfile);

            name=my_record.string;

            printf("%d : ",my_record.rec_no);
            fprintf(ptr_myfile2,"%d : ",my_record.rec_no);
            printf("%d : ",my_record.temp);
            printf("%d : ",my_record.status);
            printf("%s\n",name);
        }

    fclose(ptr_myfile);
   return 0;
}


但在25之后我看不到超过25条记录,它继续重复第25条记录...

尝试过fseek,但是它跳过了一些记录...有帮助吗?

这是输出图像



UPDATE(Wildplasser)这是数据的前0x200字节(看上去确实有点不规则...)

00000000  b8 0b 00 00 00 00 00 00  54 00 00 00 01 00 00 00  |........T.......|
00000010  42 6f 62 00 cd cd cd cd  cd cd cd cd 01 00 00 00  |Bob.............|
00000020  4d 00 00 00 00 00 00 00  43 4c 4f 53 45 44 00 cd  |M.......CLOSED..|
00000030  cd cd cd cd 02 00 00 00  2e 00 00 00 00 00 00 00  |................|
00000040  43 4c 4f 53 45 44 00 cd  cd cd cd cd 03 00 00 00  |CLOSED..........|
00000050  5f 00 00 00 01 00 00 00  48 61 72 72 79 00 cd cd  |_.......Harry...|
00000060  cd cd cd cd 04 00 00 00  44 00 00 00 01 00 00 00  |........D.......|
00000070  48 61 72 72 79 00 cd cd  cd cd cd cd 05 00 00 00  |Harry...........|
00000080  63 00 00 00 01 00 00 00  4a 69 6c 6c 00 cd cd cd  |c.......Jill....|
00000090  cd cd cd cd 06 00 00 00  53 00 00 00 01 00 00 00  |........S.......|
000000a0  4a 61 6d 65 73 00 cd cd  cd cd cd cd 07 00 00 00  |James...........|
000000b0  56 00 00 00 00 00 00 00  43 4c 4f 53 45 44 00 cd  |V.......CLOSED..|
000000c0  cd cd cd cd 08 00 00 00  49 00 00 00 00 00 00 00  |........I.......|
000000d0  43 4c 4f 53 45 44 00 cd  cd cd cd cd 09 00 00 00  |CLOSED..........|
000000e0  53 00 00 00 01 00 00 00  42 6f 62 00 cd cd cd cd  |S.......Bob.....|
000000f0  cd cd cd cd 0d 0a 00 00  00 59 00 00 00 00 00 00  |.........Y......|
00000100  00 43 4c 4f 53 45 44 00  cd cd cd cd cd 0b 00 00  |.CLOSED.........|
00000110  00 46 00 00 00 01 00 00  00 4a 69 6c 6c 00 cd cd  |.F.......Jill...|
00000120  cd cd cd cd cd 0c 00 00  00 38 00 00 00 00 00 00  |.........8......|
00000130  00 43 4c 4f 53 45 44 00  cd cd cd cd cd 0d 00 00  |.CLOSED.........|
00000140  00 48 00 00 00 00 00 00  00 43 4c 4f 53 45 44 00  |.H.......CLOSED.|
00000150  cd cd cd cd cd 0e 00 00  00 5e 00 00 00 01 00 00  |.........^......|
00000160  00 4a 61 6d 65 73 00 cd  cd cd cd cd cd 0f 00 00  |.James..........|
00000170  00 40 00 00 00 01 00 00  00 4a 69 6c 6c 00 cd cd  |.@.......Jill...|
00000180  cd cd cd cd cd 10 00 00  00 56 00 00 00 00 00 00  |.........V......|
00000190  00 43 4c 4f 53 45 44 00  cd cd cd cd cd 11 00 00  |.CLOSED.........|
000001a0  00 43 00 00 00 01 00 00  00 4a 61 6d 65 73 00 cd  |.C.......James..|
000001b0  cd cd cd cd cd 12 00 00  00 60 00 00 00 01 00 00  |.........`......|
000001c0  00 42 6f 62 00 cd cd cd  cd cd cd cd cd 13 00 00  |.Bob............|
000001d0  00 5e 00 00 00 00 00 00  00 43 4c 4f 53 45 44 00  |.^.......CLOSED.|
000001e0  cd cd cd cd cd 14 00 00  00 55 00 00 00 00 00 00  |.........U......|
000001f0  00 43 4c 4f 53 45 44 00  cd cd cd cd cd 15 00 00  |.CLOSED.........|

最佳答案

由于您的代码段不完整,很难确切说明发生了什么,但是我注意到了一些事情:


您似乎并没有使用读入的no_of_readings,而是尝试读取50条记录。由于您不检查fread的返回值,因此您的程序仅使用最后一次成功读取的fread进行操作。
如果您不阅读文本,则不应以文本模式打开文件。行尾转换可能会破坏您的数据。改用“ rb”(在文本模式下打开的标准C方式只是省略b,t是非标准)。
编辑:在Windows上,以文本模式读取文件会将ctrl-z字节(26)解释为文件结尾。这就是为什么您的读取在25条记录之后停止的原因。
像这样直接在结构中读取/写入数据将导致数据文件不可移植。最好手动将结构序列化为字节。

09-10 01:26
查看更多