C/ctype.h/iscntrl

int iscntrl(int ch)

<source lang="cpp">

//Declaration: int iscntrl(int ch); //Return: returns nonzero if ch is a control character or zero is returned.

 #include <ctype.h>
 #include <stdio.h>
 int main(void)
 {
   char ch;
   for(;;) {
      ch = getchar( );
      if(ch == ".") {
         break;
      }
      if(iscntrl(ch)){
         printf("%c is a control char\n", ch);
      }
   }
   return 0;
 }
        

/* 1

is a control char

2

is a control char

3

is a control char

.

• /

      </source>