Provided by: manpages-dev_4.04-2_all 
NAME
ttyname, ttyname_r - return name of a terminal
SYNOPSIS
#include <unistd.h> char *ttyname(int fd); int ttyname_r(int fd, char *buf, size_t buflen);
DESCRIPTION
The function ttyname() returns a pointer to the null-terminated pathname of the terminal device that is
open on the file descriptor fd, or NULL on error (for example, if fd is not connected to a terminal).
The return value may point to static data, possibly overwritten by the next call. The function
ttyname_r() stores this pathname in the buffer buf of length buflen.
RETURN VALUE
The function ttyname() returns a pointer to a pathname on success. On error, NULL is returned, and errno
is set appropriately. The function ttyname_r() returns 0 on success, and an error number upon error.
ERRORS
EBADF Bad file descriptor.
ENOTTY File descriptor does not refer to a terminal device.
ERANGE (ttyname_r()) buflen was too small to allow storing the pathname.
ATTRIBUTES
For an explanation of the terms used in this section, see attributes(7). ┌────────────┬───────────────┬────────────────────────┐ │Interface │ Attribute │ Value │ ├────────────┼───────────────┼────────────────────────┤ │ttyname() │ Thread safety │ MT-Unsafe race:ttyname │ ├────────────┼───────────────┼────────────────────────┤ │ttyname_r() │ Thread safety │ MT-Safe │ └────────────┴───────────────┴────────────────────────┘
CONFORMING TO
POSIX.1-2001, POSIX.1-2008, 4.2BSD.
SEE ALSO
fstat(2), ctermid(3), isatty(3)
COLOPHON
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