File Reading Error

[zap85]

I made a new Win32 console project with the following code. The program exits with exit code 5. It fails to read from the file just before fclose. I am facing the problem in another code. Here i have recreated the problem. Any idea what i could be doing wrong??

#include "stdafx.h"
 
int _tmain(int argc, _TCHAR* argv[])
{
    FILE *fp;
    unsigned char data[4];
    if((fp = fopen("testdump","wb+"))==NULL)
        exit(1);
    if(fwrite("text",sizeof(char)*4,1,fp)==0)
        exit(2);
    fclose(fp);
 
    if((fp = fopen("testdump","wb+"))==NULL)
        exit(3);
    if(fseek(fp, 0, SEEK_SET)!=0)
        exit(4);
    if(fread(&data[0],sizeof(char)*4,1,fp)==0)
        exit(5);
    fclose(fp);
 
    return 0;
}

[zap85]

got the ans.. the wb+ mode truncates the file to zero length before opening. i feel like an idiot..

[sicarie]

got the ans.. the wb+ mode truncates the file to zero length before opening. i feel like an idiot..

Hey, at least you figured it out. Thanks for posting the answer as well.

Maybe we can help you out with something else eventually (or maybe you can help some people here?).