is there a way to check if external data is piped to a program or if program runs on its own?

Question

That is the data is already provided by another program, or user must type it manually. I mean these two states:

dir /b /s *.* | myprogram

and

myprogram

In second case the program would be waiting for user input. Is there a way to prevent that ?

Answer 1

POSIX具有isatty() ，而Visual C ++具有_isatty() ，如果文件描述符是终端或命令行，则两者都将返回true，例如isatty(fileno(stdin)) 。

Answer 2

Yes. Use GetStdHandle to get the STD_INPUT_HANDLE and then check that the handle is of the type FILE_TYPE_PIPE in the first case or FILE_TYPE_CHAR in the second case by calling GetFileType on it.