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

This page is part of release 4.16 of the Linux man-pages project. A description of the project, information about reporting bugs, and the latest version of this page, can be found at https://www.kernel.org/doc/man−pages/.


  Copyright 2008, Linux Foundation, written by Michael Kerrisk
    <mtk.manpagesgmail.com>

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