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 ?

smocking · Accepted Answer · 2012-05-14T22:39:06.730

6

POSIX has isatty(), whereas Visual C++ has _isatty(), both of which will return true if a file descriptor is a terminal or command line, e.g. isatty(fileno(stdin)).

edited May 14 '12 at 22:39

answered May 13 '12 at 20:18

smocking

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here is interesting usage with `fileno` : http://stackoverflow.com/a/5157076/393087 – rsk82 May 14 '12 at 17:55

score 3 · Answer 2 · answered May 13 '12 at 20:08

3

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.

answered May 13 '12 at 20:08

Yakov Galka

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

2 Answers2