Home
QNX Software Development Platform
QNX SDP is a cross-compiling and debugging environment, including an IDE and command-line tools, for building binary images and programs for target boards running QNX Neutrino 7.1.
Utilities & Libraries
Utilities Reference
T
tty
Return the user's terminal name (POSIX)

QNX Momentics IDE User's Guide
This User's Guide describes version 7.1 of the Integrated Development Environment (IDE) that's part of the QNX Momentics tool suite.
QNX Software Development Platform
QNX SDP is a cross-compiling and debugging environment, including an IDE and command-line tools, for building binary images and programs for target boards running QNX Neutrino 7.1.
- Quickstart Guide
- OS Components & Operations
- Audio & Graphics API
- Multimedia
- Networking Middleware
- Programming
- Sensor Framework
- System Security Guide
  The QNX System Security Guide is intended for both system integrators who are responsible for the security of a QNX Neutrino RTOS system and developers who want to create a QNX Neutrino resource manager free from vulnerabilities.
- Utilities & Libraries
  - Addon Interfaces Library Reference
  - C Library Reference
  - Devctl and Ioctl Commands
  - JSON Library Reference
  - PAM Reference
  - Utilities Reference
    - Utility Conventions
    - A
    - B
    - C
    - D
    - E
    - F
    - G
    - H
    - I
    - J
    - K
    - L
    - M
    - N
    - O
    - P
    - Q
    - R
    - S
    - T
      - tail
        Copy the last part of files (POSIX)
      - tar
        Manipulate tape archives (UNIX)
      - tcpdump
        Dump traffic on a network
      - tee
        Duplicate standard input (POSIX)
      - telnet
        User interface to the TELNET protocol (UNIX)
      - telnetd
        DARPA TELNET protocol daemon (UNIX)
      - termdef
        Display or set the terminal type (QNX)
      - textto
        Convert text files to QNX 2, QNX 4, QNX Neutrino, UNIX, or DOS format (QNX Neutrino)
      - tftp
        Trivial file transfer program
      - tftpd
        DARPA trivial file transfer protocol daemon
      - tic
        Terminfo compiler (UNIX)
      - time
        Determine the execution time of a command (UNIX)
      - timestamp
        Write a timestamp to indicate when an event or action occurred
      - tinit
        Terminal initialization
      - top
        Display system usage (Unix)
      - touch
        Change file access and modification times (POSIX)
      - toybox
        Access common command line utilities
      - tr
        Translate characters (POSIX)
      - tracelogger
        Log tracing information into an event file
      - traceprinter
        Display the contents of the instrumented kernel trace file
      - traceroute
        Print the route packets take to network host
      - traceroute6
        Print the route IPv6 packets take to the destination
      - true
        Return true value (POSIX)
      - tsort
        Perform a topological sort of a directed graph (POSIX)
      - tty
        Return the user's terminal name (POSIX)
    - U
    - V
    - W
    - X
    - Y
    - Z
    - Commonly Used Environment Variables
    - Selecting the Target System
    - Glossary
  - WPA Control Interface Reference
    This document provides a reference for the Wi-Fi Protected Access (WPA) control interface, which provides a C API for the WPA/IEEE 802.11i protocols in Wi-Fi client stations. Application developers who want to control WPA operations and get associated status and event data should read this reference.
QNX Hypervisor
The QNX Hypervisor allows you to run multiple OSs on a target system so you can separate critical and non-critical functions, support a wide variety of applications, and reduce hardware costs.
QNX Software in the Cloud
QNX Software in the Cloud enables developers to use the QNX software in Amazon Web Services (AWS) and Microsoft Azure (Azure).
QNX Advanced Virtualization Frameworks User's Guide
This User's Guide is aimed at all systems integrators and developers who want to design and build embedded systems using the QNX Advanced Virtualization Frameworks.
Typographical Conventions, Support, and Licensing
This section describes the typographical conventions used throughout the documentation and explains how to obtain technical support.

tty

Return the user's terminal name (POSIX)

Syntax:

tty [-s]

Runs on:

QNX Neutrino

Options:

-s: Be silent; don't output the terminal name. This option is useful if you're concerned only with tty's exit status.

Description:

The tty utility writes to the standard output the name of the terminal that's open as standard input. If standard input isn't a terminal (e.g., it's a file such as /dev/null), the string not a tty is output instead.

Note:

The -s option is deprecated by POSIX; you can achieve the effect of this option, simply and portably, by redirecting output to /dev/null or by using the shell builtin, test -c.
QNX Neutrino also supports a toybox version of this utility. For more information, go to the toybox entry of this reference.

Examples:

The following command prints /dev/con1 if run on console 1:

tty

The following command prints not a tty because /dev/null causes isatty() to return 0:

tty </dev/null

Exit status:

0: Success.
> 0: An error occurred.

Page updated: March 12, 2026