"punctuation" includes all printing characters that are neither alphanumeric nor a space.
#include <ctype.h> #include <stdio.h> int main(void) { char ch; for(;;) { ch = getchar(); if(ispunct(ch)){ printf("%c is punctuation\n", ch); } if(ch == '.'){ break; } } return 0; }
fd d w s d . . is punctuation