usr/src/include/ctype.h

/*      ctype.h 4.2     85/09/04        */

#define _U      01
#define _L      02
#define _N      04
#define _S      010
#define _P      020
#define _C      040
#define _X      0100
#define _B      0200

extern  char    _ctype_[];

#define isalpha(c)      ((_ctype_+1)[c]&(_U|_L))
#define isupper(c)      ((_ctype_+1)[c]&_U)
#define islower(c)      ((_ctype_+1)[c]&_L)
#define isdigit(c)      ((_ctype_+1)[c]&_N)
#define isxdigit(c)     ((_ctype_+1)[c]&(_N|_X))
#define isspace(c)      ((_ctype_+1)[c]&_S)
#define ispunct(c)      ((_ctype_+1)[c]&_P)
#define isalnum(c)      ((_ctype_+1)[c]&(_U|_L|_N))
#define isprint(c)      ((_ctype_+1)[c]&(_P|_U|_L|_N|_B))
#define isgraph(c)      ((_ctype_+1)[c]&(_P|_U|_L|_N))
#define iscntrl(c)      ((_ctype_+1)[c]&_C)
#define isascii(c)      ((unsigned)(c)<=0177)
#define toupper(c)      ((c)-'a'+'A')
#define tolower(c)      ((c)-'A'+'a')
#define toascii(c)      ((c)&0177)