### isblank -- Test for Blank Character Classification

Format

>     #include <ctype.h>
>     int isblank(int c);

Language Level: Extension
isblank tests whether the current LC_CTYPE locale category assigns c the blank character attribute.

The value for c must be representable as an unsigned character, or EOF.

In the "POSIX" and "C" locales, the tab and space characters have the blank attribute.

Return Value
isblank returns a nonzero value if the integer c has the blank attribute; 0 if it does not.

Example
This example tests if c is a blank type.

    #include <ctype.h>
    #include <locale.h>
    #include <stdio.h>

    void check(char c) {
       if ((' ' != c) && (isprint(c)))
          printf("  %c is ", c);
       else
          printf("x%02x is ", c);
       if (!isblank(c))
          printf("not ");
       puts("a blank type character");
       return;
    }

    int main(void)
    {
       printf("In LC_CTYPE category of locale name \"%s\":\n",
              setlocale(LC_CTYPE, NULL));
       check('a');
       check(' ');
       check(0x00);
       check('\n');
       check('\t');
       return 0;

       /*******************************************************
          The output should be similar to:

          In LC_CTYPE category of locale name "C":
            a is not a blank type character
          x20 is a blank type character
          x00 is not a blank type character
          x0a is not a blank type character
          x09 is a blank type character
       *******************************************************/
    }

isalnum to isxdigit -- Test Integer Value
isascii -- Test Integer Values
_iscsym -- _iscsymf -- Test Integer
iswalnum to iswxdigit -- Test Wide Integer
iswblank -- Test for Wide Blank Character Classification
setlocale -- Set Locale
<ctype.h>