isatty() tests if file descriptor is associated with terminal device	Function
	SYNOPSIS DESCRIPTION PARAMETERS RETURN VALUES CONFORMANCE MULTITHREAD SAFETY LEVEL PORTING ISSUES AVAILABILITY SEE ALSO

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SYNOPSIS

#include <unistd.h>

int isatty(int fildes);

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DESCRIPTION

The isatty() function tests whether the specified file descriptor is associated with a terminal device.

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PARAMETERS

fildes 

Is the file descriptor to test.

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RETURN VALUES

If the file descriptor fildes describes a terminal, isatty() returns a value of 1. If fildes is not a terminal, isatty() returns a value of zero, and sets errno to one of the following values:

ENOTTY 

The fildes parameter is not associated with a terminal.

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CONFORMANCE

UNIX 98.

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MULTITHREAD SAFETY LEVEL

MT-Safe.

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PORTING ISSUES

None.

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AVAILABILITY

PTC MKS Toolkit for Professional Developers
PTC MKS Toolkit for Professional Developers 64-Bit Edition
PTC MKS Toolkit for Enterprise Developers
PTC MKS Toolkit for Enterprise Developers 64-Bit Edition

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SEE ALSO

Functions:

ttyname(), ttyname_r()

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PTC MKS Toolkit 10.5 Documentation Build 40.