NAME

zkIsatty - test for a terminal device

SYNOPSIS

#include "zkUnistd.h"

int zkIsatty(int fildes);

DESCRIPTION

The zkIsatty() function tests whether fildes, an open file descriptor, is associated with a terminal device.

RETURN VALUE

The zkIsatty() function returns 1 if fildes is associated with a terminal; otherwise it returns 0 and may set errno to indicate the error.

ERRORS

The zkIsatty() function may fail if:

[EBADF]
The fildes argument is not a valid open file descriptor.
[ENOTTY]
The fildes argument is not associated with a terminal.

APPLICATION USAGE

The zkIsatty() function does not necessarily indicate that a human being is available for interaction via fildes. It is quite possible that non-terminal devices are connected to the communications line.