ISATTY

Section: Linux Programmer's Manual (3)
Updated: 2015-08-08
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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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Index

NAME

SYNOPSIS

DESCRIPTION

RETURN VALUE

ERRORS

ATTRIBUTES

CONFORMING TO

SEE ALSO

COLOPHON