Scanf question

[mdh]

Scanf ( sect 7.4) contains this description...


On end of file, EOF is returned: note this is different from 0


"which means that the next input character does not match the first
specification in the format string"


Could someone perhaps elaborate on the line in quotes, (not the value
of EOF not being zero).

Thank you.

 

[Andrew Poelstra]

Scanf ( sect 7.4) contains this description...


On end of file, EOF is returned: note this is different from 0


"which means that the next input character does not match the first
specification in the format string"


Could someone perhaps elaborate on the line in quotes, (not the value
of EOF not being zero).

I believe it means that scanf() will return 0 if it cannot
process the first format specifier with the first ("next")
input character.

OTOH, EOF means it ran out of input characters altogether.

 

[mdh]

I believe it means that scanf() will return 0 if it cannot
process the first format specifier with the first ("next")
input character.

OTOH, EOF means it ran out of input characters altogether.

So, this should in essence stop any further processing of this format
specifier and should leave the input untouched?

thank you Andrew

 

[mdh]

mdh wrote: "

BEGIN new.c output

a
That's not an int value.

END new.c output

/* BEGIN new.c */

#include <stdio.h>

int main(void)
{
     int a;

     puts("BEGIN new.c output\n");
     if (scanf("%d", &a) == 0) {
         puts("That's not an int value.");
     }
     puts("\nEND new.c output");
     return 0;

}

/* END new.c */

Thanks Pete.. nice demo.

 

[Peter Nilsson]

So, this should in essence stop any further processing
of this format specifier and should leave the input
untouched?

Whitespace will still be skipped where applicable. However,
in all cases, "The first character, if any, after the input
item remains unread."