isatty (3)

Leading comments

Copyright 2008, Linux Foundation, written by Michael Kerrisk
    <mtk.manpages@gmail.com>

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(The comments found at the beginning of the groff file "man3/isatty.3".)

NAME

isatty - test whether a file descriptor refers to a terminal

SYNOPSIS

#include <unistd.h>

int isatty(int fd);

DESCRIPTION

The isatty() function tests whether fd is an open file descriptor referring to a terminal.

RETURN VALUE

isatty() returns 1 if fd is an open file descriptor referring to a terminal; otherwise 0 is returned, and errno is set to indicate the error.

ERRORS

EBADF

fd is not a valid file descriptor.

EINVAL

fd refers to a file other than a terminal. POSIX.1 specifies the error ENOTTY for this case.

ATTRIBUTES

For an explanation of the terms used in this section, see attributes(7).

Interface	Attribute	Value
isatty()	Thread safety	MT-Safe

CONFORMING TO

POSIX.1-2001, POSIX.1-2008, SVr4, 4.3BSD.

SEE ALSO

fstat(2), ttyname(3)

COLOPHON

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