Programming

between below program that spits out 0 for EOF and /usr/include/stdio.h, which has , I am bit confused. I ran below program and I do get 0 for EOF..

can someone please help bit further..

/* End of file character.
Some things throughout the library rely on this being -1. */
#ifndef EOF
# define EOF (-1)
#endif

/* This program prompts for input, and then captures a character
* from the keyboard. If EOF is signalled (typically through a
* control-D or control-Z character, though not necessarily),
* the program prints 0. Otherwise, it prints 1.
*
* If your input stream is buffered (and it probably is), then
* you will need to press the ENTER key before the program will
* respond.
*/

#include <stdio.h>

int main(void)
{
printf("Press a key. ENTER would be nice :-)\n\n");
printf("The expression getchar() != EOF evaluates to %d\n", getchar() != EOF);
return 0;
}

8 bit characters are between 0 and 255. EOF has to be outside that range, hence why getchar and fgetc return an int and not a char. If you read that into a char it will work (a) if char is naturally signed (b) character 255 does not appear in the data stream.