ref: ca543c97d5f35334bc9784a3b5c7c5a8fe7a8f8a dir: /lib/c/isprint.c/
#define __USE_MACROS #include <ctype.h> #undef isprint int isprint(int c) { return (__ctype+1)[c] & (_P|_U|_L|_D|_SP); }