isprint() Prototype
int isprint(int ch);
The isprint() function checks if ch is printable as classified by the current C locale. By default, the following characters are printable:
- Digits (0 to 9)
- Uppercase letters (A to Z)
- Lowercase letters (a to z)
- Punctuation characters (!"#$%&'()*+,-./:;<=>?@[\]^_`{|}~)
- Space
The behaviour of isprint() is undefined if the value of ch is not representable as unsigned char or is not equal to EOF.
It is defined in <cctype> header file.
isprint() Parameters
ch: The character to check.
isprint() Return value
The isprint() function returns non zero value if ch is printable, otherwise returns zero.
Example: How isprint() function works
#include <cctype>
#include <iostream>
#include <cstring>
using namespace std;
int main()
{
char str[] = "Hello\tall\nhow are you";
for (int i=0; i<strlen(str); i++)
{
/* replace all non printable character by space */
if (!isprint(str[i]))
str[i] = ' ';
}
cout << str;
return 0;
}
When you run the program, the output will be:
Hello all how are you