what is the reason for fopen's failure to open a file

Question

I have the following code where I am trying to open a text file.

char frd[32]="word-list.txt";
   FILE *rd=fopen(frd,"rb");
   if(!rd)
       std::cout<<"Coudn't open file\t"<<frd;

I am using vc 2010 and the file is in the debug directory of this project. Can anyone tell me why it is not able to open the file?

Answer 1

#include<stdio.h>
#include <errno.h>

int main()
{
errno = 0;
FILE *fb = fopen("/home/jeegar/filename","r");
if(fb==NULL)
    printf("its null");
else
    printf("working");


printf("Error %d \n", errno);


}

this way if fopen gets fail then it will set error number you can find those error number list at here http://pubs.opengroup.org/onlinepubs/009695399/functions/fopen.html

Answer 2

Look at the errno variable which is set in the event of an error. It's a global variable. It's been a while, but probably include errno.h which will give you the definition.