Check input device is a terminal: Difference between revisions

We use the interface to C library functions <code>isatty()</code> and <code>fileno()</code>.

 

with Interfaces.C_Streams; use Interfaces.C_Streams;

 

Put_Line(Standard_Error, "stdin is a tty.");

end if;

 

{{out}}

 

=={{header|BaCon}}==

 

{{out}}

=={{header|C}}==

Use <code>isatty()</code> on file descriptor to determine if it's a TTY. To get the file descriptor from a <code>FILE*</code> pointer, use <code>fileno</code>:

#include <stdio.h> //for fileno()

 

: "stdin is not tty");

return 0;

{{out}}

<pre>

Works with GnuCOBOL.

 

*> istty, check id fd 0 is a tty

*> Tectonics: cobc -xj istty.cob

 

goback.

 

DISPLAY for fd 1 is directed to SYSERR to get some output during the various trials.

=={{header|Common Lisp}}==

{{Works with|SBCL}}

(format T "stdin is~:[ not~;~] a terminal~%"

 

{{Out}}

 

=={{header|Crystal}}==

File.new("/dev/tty").tty? #=> true

 

=={{header|D}}==

 

extern(C) int isatty(int);

else

writeln("Input doesn't come from tty.");

{{out}}

<pre>C:\test

 

=={{header|FreeBASIC}}==

Open Cons For Input As #1

' Open Cons abre los flujos de entrada (stdin) o salida (stdout) estándar

Close #1

Sleep

 

 

=={{header|Go}}==

{{libheader|Go sub-repositories}}

 

import (

fmt.Println("Who are you? You're not a terminal.")

}

{{out}}

<pre>

Example uses [https://hackage.haskell.org/package/unix <tt>unix</tt>] package:

 

import System.Posix.IO (stdInput)

putStrLn $ if isTTY

then "stdin is TTY"

 

=={{header|Jsish}}==

;Interp.conf().subOpts.istty;

 

Interp.conf().subOpts.istty ==> false

=!EXPECTEND!=

 

{{out}}

 

=={{header|Julia}}==

if isa(STDIN, Base.TTY)

println("This program sees STDIN as a TTY.")

println("This program does not see STDIN as a TTY.")

end

 

{{out}}

=={{header|Kotlin}}==

{{Works with|Ubuntu|14.04}}

 

import platform.posix.*

println("stdin is not a terminal")

}

 

{{out}}

=={{header|Nemerle}}==

There is no explicit way (ie <tt>isatty()</tt>)to do this; however, if we ''assume'' that standard input ''is'' a terminal, we can check if the input stream has been redirected (presumably to something other than a terminal).

 

=={{header|Nim}}==

Using function "isatty" of standard module "terminal" which accepts a File as argument.

 

 

 

{{out}}

=={{header|OCaml}}==

 

print_endline (

if Unix.isatty Unix.stdin

then "Input comes from tty."

else "Input doesn't come from tty."

 

Testing in interpreted mode:

 

=={{header|Ol}}==

(define (isatty? fd) (syscall 16 fd 19))

(print (if (isatty? stdin)

"Input comes from tty."

"Input doesn't come from tty."))

 

=={{header|Perl}}==

use warnings;

use 5.010;

else {

say "Input doesn't come from tty.";

 

$ perl istty.pl

 

=={{header|Phix}}==

<span style="color: #008080;">without</span> <span style="color: #008080;">js</span> <span style="color: #000080;font-style:italic;">-- (no input redirection in a browser!)</span>

<span style="color: #7060A8;">printf</span><span style="color: #0000FF;">(</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,</span><span style="color: #008000;">"stdin:%t, stdout:%t, stderr:%t\n"</span><span style="color: #0000FF;">,{</span><span style="color: #000000;">isatty</span><span style="color: #0000FF;">(</span><span style="color: #000000;">0</span><span style="color: #0000FF;">),</span><span style="color: #000000;">isatty</span><span style="color: #0000FF;">(</span><span style="color: #000000;">1</span><span style="color: #0000FF;">),</span><span style="color: #000000;">isatty</span><span style="color: #0000FF;">(</span><span style="color: #000000;">2</span><span style="color: #0000FF;">)})</span>

{{out}}

<pre>

 

=={{header|Pike}}==

{

if(Stdio.Terminfo.is_tty())

else

write("Input doesn't come from tty.\n");

 

{{out}}

 

=={{header|Python}}==

if stdin.isatty():

print("Input comes from tty.")

else:

 

$ python istty.py

{{trans|Python}}

 

to_stack( 1 if stdin.isatty() else 0)|

python ] is ttyin ( --> b )

[ say "Looks like a teletype." ]

else

 

{{out}}

 

=={{header|Racket}}==

(terminal-port? (current-input-port))

 

=={{header|Raku}}==

(formerly Perl 6)

{{works with|Rakudo|2015.12}}

 

$ raku istty.raku

 

=={{header|REXX}}==

 

if queued() then say 'input comes from the terminal.'

 

/*stick a fork in it, we're done.*/

 

=={{header|Ring}}==

# Project : Check input device is a terminal

see SystemCmd("mycmd.bat")

ok

Output:

<pre>

=={{header|Ruby}}==

Example from the docs.

 

=={{header|Rust}}==

 

extern crate libc;

println!("stdout is not tty");

}

 

=={{header|Scala}}==

{{Works with|Ubuntu|14.04}}

 

object IsATty extends App {

 

println("tty " + apply(true))

 

=={{header|Standard ML}}==

 

=={{header|Tcl}}==

Tcl automatically detects whether <tt>stdin</tt> is coming from a terminal (or a socket) and sets up the channel to have the correct type. One of the configuration options of a terminal channel is <tt>-mode</tt> (used to configure baud rates on a real serial terminal) so we simply detect whether the option is present.

puts "Input doesn't come from tty."

} else {

puts "Input comes from tty."

Demonstrating:

<pre>

 

=={{header|UNIX Shell}}==

 

if [ -t 0 ]

else

echo "Input is NOT a terminal"

 

=={{header|Wren}}==

 

 

{{out}}

=={{header|zkl}}==

On Unix, check to see if stdin's st_mode is a character device.

fcn S_ISCHR(f){ f.info()[4].bitAnd(S_IFCHR).toBool() }

{{out}}

<pre>