Usage and example of C library function ispunct()

C Standard Library <ctype.h>

ispunct() function checks whether a character is a punctuation symbol.

The prototype of ispunct() function is:

int ispunct(int argument);

If the character passed to the ispunct() function is a punctuation symbol, it returns a non-zero integer. If not, it returns 0.

In C language programming, char characters are internally treated as integers. This is why ispunct() uses an integer parameter.

The ispunct() function inctype.hDefined in header files.

Example1Check punctuation program

#include <stdio.h>
#include <ctype.h>
int main() {
　　　char c;
　　　int result;
　　　c = ':';
　　　result = ispunct(c);
　　　if (result == 0) {
　　　　　　printf("%c is not a punctuation symbol", c);
　　　} else {
　　　　　　printf("%c is a punctuation symbol", c);
　　　}
　　　return 0;
}

Output Result

: It is a punctuation symbol

Example2Print all punctuations

#include <stdio.h>
#include <ctype.h>
int main()
{
　　　　int i;
　　　　printf("All punctuation symbols in C:\n");
　　　　//traverse all ASCII characters
　　　　for (i = 0; i <=　127;　++i)
　　　　　　　　if (ispunct(i) != 0)
　　　　　　　　　　　　printf("%c ", i);
　　　　return 0;
}

Output Result

All Punctuation Symbols in C:　
! " # $ % & ' ( )　*　+　,　-　.　/　: ; < = > ? @ [ \ ] ^ _ ` { | } ~

C Standard Library <ctype.h>