Learn competitive and Technical Aptitude C programming mcq questions and answers on File I/O with easy and logical explanations. Page-4 section-1
FILE is a pre-defined structure.
Besides the file pointers which we explicitly open by calling fopen, there are also three predefined streams. stdin is a constant file pointer corresponding to standard input, and stdout is a constant file pointer corresponding to standard output. Both of these can be used anywhere when a file pointer is called for; for example, getchar() is the same as getc(stdin) and putchar(c) is the same as putc(c, stdout). The third predefined stream is stderr. Like stdout, stderr is typically connected to the screen by default. The difference is that stderr is not redirected when the standard output is redirected.
#include <stdio.h>
struct p
{
struct p *next;
int x;
};
int main()
{
struct p* p1 = malloc(sizeof(struct p));
p1->x = 1;
p1->next = malloc(sizeof(struct p));
printf("%d\n", p1->next->x);
return 0;
}