### _iscsym - _iscsymf -- Test Integer

Format

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

Language Level: Extension
These macros test if an integer is within a particular ASCII set. The macros assume that the system uses the ASCII character set.

_iscsym tests if a character is alphabetic, a digit, or an underscore (_). _iscsymf tests if a character is alphabetic or an underscore.

Return Value
_iscsym and _iscsymf return a nonzero value if the integer is within the ASCII set for which it tests, and 0 if it is not.

Example
This example uses _iscsym and _iscsymf to test the characters a, _, and 1. If the character falls within the ASCII set tested for, the macro returns TRUE. Otherwise, it returns FALSE.

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

    int main(void)
    {
       int ch[3] =  { 'a','_','1' };
       int i;

       for (i = 0; i < 3; i++) {
          printf("_iscsym('%c') returns %s\n", ch[i], _iscsym(ch[i])?"TRUE":"FALSE");
          printf("_iscsymf('%c') returns %s\n\n", ch[i], _iscsymf(ch[i])?"TRUE":
             "FALSE");
       }
       return 0;

       /****************************************************************************
          The output should be:

          _iscsym('a') returns TRUE
          _iscsymf('a') returns TRUE

          _iscsym('_') returns TRUE
          _iscsymf('_') returns TRUE

          _iscsym('1') returns TRUE
          _iscsymf('1') returns FALSE
       ****************************************************************************/
    }

isalnum to isxdigit -- Test Integer Value
isascii -- Test Integer Values
isblank -- Test for Blank Character Classification
iswalnum to iswxdigit -- Test Wide Integer Value
iswblank -- Test for Wide Blank Character Classification
tolower - toupper -- Convert Character Case
_toascii - _tolower - _toupper -- Convert Character
<ctype.h>