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/dev/ttyb missing from UBUNTU
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tty(1) General Commands Manual tty(1) NAME
tty - Returns pathname of terminal device SYNOPSIS
tty [-s] The tty command writes the full pathname of your terminal device to standard output. The tty command may also be used to determine if standard input is a terminal. STANDARDS
Interfaces documented on this reference page conform to industry standards as follows: tty: XCU5.0 Refer to the standards(5) reference page for more information about industry standards and associated tags. OPTIONS
Suppresses reporting the pathname. The XCU specification states that -s option is obsolete and recommends the portable applications use test -t 0 instead of tty -s. OPERANDS
None DESCRIPTION
The command tty -s evaluates as TRUE if standard input is a display and FALSE if it is not. [Tru64 UNIX] The file /dev/tty is a special file always refers to your controlling terminal, although it also may have another name like /dev/console or /dev/tty2. To avoid writing undesirable output to an output file--for example, to write a prompt in a shell script to the screen, while writing the response to the prompt to an output file--redirect standard output to /dev/tty. NOTES
While the -s option is useful if only the exit code is wanted, it does not rely on any ability to form a valid pathname. For a portable application you should use the command test -t 0. EXIT STATUS
The following exit values are returned: Successful completion. Standard input is not a display. [Tru64 UNIX] Invalid options specified. [Tru64 UNIX] An error occurred. DIAGNOSTICS
[Tru64 UNIX] Your standard input is not a display and you did not specify the -s option. EXAMPLES
To display full pathname of your terminal device, enter: tty To test whether or not the standard input is a terminal device, create a shell script containing the following: if tty -s then echo 'Output is a display' else echo 'Output is not a display' fi If the standard input is a terminal device, this displays the Output is a display message. If the standard input is not a terminal device, it displays the Output is not a display message. ENVIRONMENT VARIABLES
The following environment variables affect the execution of tty: Provides a default value for the internationalization variables that are unset or null. If LANG is unset or null, the corresponding value from the default locale is used. If any of the internationalization vari- ables contain an invalid setting, the utility behaves as if none of the variables had been defined. If set to a non-empty string value, overrides the values of all the other internationalization variables. Determines the locale for the interpretation of sequences of bytes of text data as characters (for example, single-byte as opposed to multibyte characters in arguments). Determines the locale for the for- mat and contents of diagnostic messages written to standard error. Determines the location of message catalogues for the processing of LC_MESSAGES. FILES
Pseudodevice representing the user's controlling terminal. SEE ALSO
Commands: stty(1), test(1) Routines: ttyname(3) Files: tty(7) Standards: standards(5) tty(1)
