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)

Information

Source
Linux kernel
OS/version
Linux
Source updated
August 8, 2015
Page created
February 9, 2018
Page generated
December 2, 2018