foo.cpp: In function 'void io::init()':
foo.cpp:12:48: error: '_fread_nolock' was not declared in this scope
         T = S+_fread_nolock(B, 1, MAXBUF, stdin);
                                                ^
foo.cpp: In function 'void io::output()':
foo.cpp:65:67: error: '_fwrite_nolock' was not declared in this scope
  inline void output() {_fwrite_nolock(buff, 1, iter - buff, stdout), iter = buff;}
                                                                   ^