scanf check for EOF

[mcauliff]

How is end of file or no input check done for scanf?

example;

for (n = 0; n < 10; ++n) {
printf("enter a number\n");
scanf ("%d", %int);
if (int == "")
break;
}

 

[macd68]

By including stdio.h and doing the intuitive thing.

int p = 0;
for (i=0; i < 10 ; i++) {
    printf("\nEnter integer value:");
    scanf(" %d",&p);
    if (p == EOF) {printf("Eof encountered\n");
}

 

[mcauliff]

What is wrong with this code?

/* scanf check for EOF */

#include <stdio.h>

int main() {
int n, i;
for (i = 0; i < 5; ++i) {
printf ("enter a single digit or hit enter \n");
scanf(" %d", &n);
if (n == EOF)
break;
printf("%d\n", n);
}
return 0;
}

 

[Salem]

scanf returns EOF, it doesn't store it in the result.

As in

int result = scanf( "%d", &value );
if ( result == EOF ) {
  // yes, th th th th that's all folks
}

--
If you dance barefoot on the broken glass of undefined behaviour, you've got to expect the occasional cut.

 

[ArkM]

On success scanf returns the number of fields successfully converted and assigned (1 in your case).
So any unusual condition (i/o error, EOF etc) test is:

if (scanf("%d",&n) != 1)
... break ...