ttyname_r(3) - Linux man page

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.

Conforming to

4.2BSD, POSIX.1-2001.