Question

While debugging some code I got something like below:

#include<stdio.h>

int main()
{
    FILE *fb = fopen("/home/jeegar/","r");
    if(NULL == fb)
        printf("it is null");
    else
        printf("working");
}

Here in fopen I gave a somewhat valid path name but not a filename. Shouldn’t fopen return NULL then? But it does not return null!

Edit:

If I give path of valid directory in fopen then it will print working:

If I give path of invalid directory in fopen then it will print it is null

Edit:
spec says

Upon successful completion, fopen() shall return a pointer to the object 
controlling the stream. Otherwise, a null pointer shall be returned.

so here whether error code set or not, it MUST return NULL

And error code setting is an extansion to ISO C standard standard.

ERROR IS ALSO NOT GOING TO SET HERE

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

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


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


}

OUTPUT IS

workingError 0 

Answer 1

I think that in Unix everything (directories included) is considered to be file so fopen should work on them.