TTYNAME

Section: C Library Functions (3)
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BSD mandoc

NAME

ttyname isatty ttyslot - get name of associated terminal (tty) from file descriptor

SYNOPSIS

Fd #include <unistd.h> Ft char * Fn ttyname int fd Ft int Fn isatty int fd Ft int Fn ttyslot

DESCRIPTION

These functions operate on the system file descriptors for terminal type devices. These descriptors are not related to the standard I/O FILE typedef, but refer to the special device files found in /dev and named /dev/tty xx and for which an entry exists in the initialization file /etc/ttys. (See ttys(5).)

The Fn isatty function determines if the file descriptor Fa fd refers to a valid terminal type device.

The Fn ttyname function gets the related device name of a file descriptor for which Fn isatty is true

The Fn ttyslot function fetches the current process' control terminal number from the ttys(5) file entry.

RETURN VALUES

The Fn ttyname function returns the null terminated name if the device is found and Fn isatty is true; otherwise a NULL pointer is returned.

The Fn ttyslot function returns the unit number of the device file if found; otherwise the value zero is returned.

FILES

/dev/*
/etc/ttys

HISTORY

A Fn isatty , Fn ttyname , and Fn ttyslot function appeared in AT&T System v7 .

BUGS

The Fn ttyname function leaves its result in an internal static object and returns a pointer to that object. Subsequent calls to Fn ttyname will modify the same object.

This document was created by man2html, using the manual pages.
Time: 19:41:58 GMT, December 25, 2022