Important Notice

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─────Run-Time Library───────────────────────────────────────────────────────
 
  Include:   <ctype.h>
 
  Syntax:    int isalnum( int c );     (alphanumeric character)
             int isalpha( int c );     (alphabetic character)
             int __isascii( int c );   (ASCII character)
             int iscntrl( int c );     (control character)
             int __iscsym( int c );    (letter, underscore, or digit)
             int __iscsymf( int c );   (letter or underscore)
             int isdigit( int c );     (decimal digit)
             int isgraph( int c );     (printable character, not space)
             int islower( int c );     (lowercase letter)
             int isprint( int c );     (printable character)
             int ispunct( int c );     (punctuation character)
             int isspace( int c );     (white-space character)
             int isupper( int c );     (uppercase letter)
             int isxdigit( int c );    (hexadecimal digit)
 
  Returns:   a nonzero value if the condition is true, or 0 if it
             is not.
 
  See also:  __toascii, tolower, toupper
                                    -♦-