CODEWITHSUNDEEP
cfilepointers
NobToJuneau
NobToJuneau

Reputation: 15

Why can't the FILE pointer can't read the contents in the file?

I'm trying to get the contents from the file yh.dat which HAS the text like "456 78921" and somthing else by C.But when I try debug the code,the FILE pointer isn't NULL(0x00428af8) and the _ptr and the _base is NULL(0x000000).They says "CXX0030:Error:expression cannot be evaluated".How to solve it?

int main(){
   FILE *fp=NULL;
   fp=fopen("yh.dat","rb");
   if(fp==NULL)
   {
        printf("error");
    exit(0);
   }
   return 0;
}

Upvotes: 0

Views: 659

Answers (1)

Jerry Coffin
Jerry Coffin

Reputation: 490663

To allow you to change the file buffering, C doesn't set up the buffer for a file until you issue the first read. As such, until you attempt at least one read, it's normal for the members of whatever struct the FILE * points at to be in an only semi-initialized state.

Have you tried just reading data to see if it works?

Upvotes: 2

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