ctype.h

   1 #ifndef _CTYPE_H
   2 #define _CTYPE_H
   3
   4 int isascii(int c);
   5 int isblank(int c);
   6 int isspace(int c);
   7 int isalpha(int c);
   8 int isdigit(int c);
   9 int isalnum(int c);
  10 int isupper(int c);
  11 int islower(int c);
  12 int isprint(int c);
  13
  14 int tolower(int c);
  15 int toupper(int c);
  16
  17 #endif