1 // 2 // isatty.cpp 3 // 4 // Copyright (c) Microsoft Corporation. All rights reserved. 5 // 6 // Defines _isatty(), which tests whether a file refers to a character device. 7 // 8 #include <corecrt_internal_lowio.h> 9 10 11 12 // Tests if the given file refers to a character device (e.g. terminal, console, 13 // printer, serial port, etc.). Returns nonzero if so; zero if not. 14 extern "C" int __cdecl _isatty(int const fh) 15 { 16 _CHECK_FH_RETURN(fh, EBADF, 0); 17 _VALIDATE_RETURN((fh >= 0 && (unsigned)fh < (unsigned)_nhandle), EBADF, 0); 18 19 return static_cast<int>(_osfile(fh) & FDEV); 20 } 21