getchar example from K&R C does not work properly -

i wondering what's happening in code k&r c:

#include <stdio.h>  int main() {     double nc;      (nc = 0; getchar(); ++nc) {         ;     }     printf("%.0f\n", nc); }

when run code (os x el capitan), for loop doesn't finish , can't printf statement.

the getchar() returns obtained character on success or eof on failure. reference here.

try this

for (nc = 0; getchar() != eof; ++nc) { }

note that, enter doesn't means eof, means newline or '\n'.

look @ header stdio.h, says,

#define eof (-1)

here can see how simulate eof.

windows: ctrl+z unix :   ctrl+d

so long story short, can put condition in for loop,

for (nc = 0; getchar() != '\n'; ++nc) { } // break loop if enter pressed (nc = 0; getchar() != 'c'; ++nc) { } // break loop if c pressed . . .

Overvie