selftests: Testing a write attempt into a full file?

[SF Markus Elfring]

Hello,

I have constructed another demonstration program.


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

int main(void)
{
        FILE *f = fopen("/dev/full", "a");

        if (!f)
                goto report_failure;

        {
        int const c = 'X';

        if (fputc(c, f) != c)
                goto report_failure;
        }

        return EXIT_SUCCESS;

report_failure:
        perror(__func__);
        return errno;
}


I got the following result.

elfring@Sonne:~/Projekte/selftests> gcc-7 putc_into_full_file1.c && ./a.out; 
echo $?
0


Does such a simple test example need further software development 
considerations?

Regards,
Markus