Terminal control/Dimensions

Terminal control/Dimensions
You are encouraged to solve this task according to the task description, using any language you may know.

Determine the height and width of the terminal, and store this information into variables for subsequent use.

Applesoft BASIC

<lang ApplesoftBasic>WIDTH = PEEK(33) HEIGHT = PEEK(35) - PEEK(34)</lang>

AutoHotkey

Works with: AutoHotkey_L

Translation of: C

AutoHotkey is not built for the console (it is GUI oriented) so we must call the WinAPI directly. <lang AHK>DllCall( "AllocConsole" ) ; create a console if not launched from one hConsole := DllCall( "GetStdHandle", int, STDOUT := -11 )

MsgBox Resize the console...

VarSetCapacity(csbi, 22) ; CONSOLE_SCREEN_BUFFER_INFO structure DllCall("GetConsoleScreenBufferInfo", UPtr, hConsole, UPtr, &csbi) Left  := NumGet(csbi, 10, "short") Top  := NumGet(csbi, 12, "short") Right  := NumGet(csbi, 14, "short") Bottom := NumGet(csbi, 16, "short")

columns := right - left + 1 rows := bottom - top + 1 MsgBox %columns% columns and %rows% rows</lang>

Axe

Since Axe currently only supports the TI-83/84, the home screen dimensions are fixed at 16 columns by 8 rows.

Batch File

Screen Buffer Size: <lang dos>@echo off

for /f "tokens=1,2 delims= " %%A in ('mode con') do ( if "%%A"=="Lines:" set line=%%B if "%%A"=="Columns:" set cols=%%B )

echo Lines: %line% echo Columns: %cols% exit /b 0</lang>

Output:

>Size.Bat
Lines: 300
Columns: 80

>

BBC BASIC

Works with: BBC BASIC for Windows

<lang bbcbasic> dx% = @vdu.tr%-@vdu.tl% : REM Width of text viewport in pixels

     dy% = @vdu.tb%-@vdu.tt% : REM Height of text viewport in pixels</lang>

C

C provides no standard way to find the size of a terminal.

Library: BSD libc

BSD systems (and some other Unix clones) have TIOCGWINSZ. This ioctl(2) call gets the "window size" of a tty(4) device.

Almost all terminal devices can do NAWS (Negotiate About Window Size). A terminal emulator like xterm(1) should set the size. A network server like sshd(1) should copy the size from its client. Other devices, such as plain serial ports, might not know the window size.

Works with: BSD version 4.4

<lang c>#include <sys/ioctl.h> /* ioctl, TIOCGWINSZ */

1. include <err.h> /* err */
2. include <fcntl.h> /* open */
3. include <stdio.h> /* printf */
4. include <unistd.h> /* close */

int main() { struct winsize ws; int fd;

/* Open the controlling terminal. */ fd = open("/dev/tty", O_RDWR); if (fd < 0) err(1, "/dev/tty");

/* Get window size of terminal. */ if (ioctl(fd, TIOCGWINSZ, &ws) < 0) err(1, "/dev/tty");

printf("%d rows by %d columns\n", ws.ws_row, ws.ws_col); printf("(%d by %d pixels)\n", ws.ws_xpixel, ws.ws_ypixel);

close(fd); return 0; }</lang>

Windows

Grab a console screen handle, then call GetConsoleScreenBufferInfo() to get the information. Most consoles have a scroll bar and hold hundreds of lines, but the window shows only 25 or 50 lines. Use the window coordinates to calculate the window size.

Works with: MinGW

<lang c>#include <windows.h>

1. include <wchar.h>

int main() { HANDLE console; CONSOLE_SCREEN_BUFFER_INFO info; short rows; short columns; /* Create a handle to the console screen. */ console = CreateFileW(L"CONOUT$", GENERIC_READ | GENERIC_WRITE, FILE_SHARE_READ | FILE_SHARE_WRITE, NULL, OPEN_EXISTING, 0, NULL); if (console == INVALID_HANDLE_VALUE) return 1;

/* Calculate the size of the console window. */ if (GetConsoleScreenBufferInfo(console, &info) == 0) return 1; CloseHandle(console); columns = info.srWindow.Right - info.srWindow.Left + 1; rows = info.srWindow.Bottom - info.srWindow.Top + 1;

wprintf(L"%d columns by %d rows\n", columns, rows);

return 0; }</lang>

C#

The C# console has several properties to take note of. BufferHeight and BufferWidth are the valid writing area, the cursor can print anywhere within these bounds. This can be considered the actual terminal. WindowHeight and WindowWidth are simply the size of the window, it only represents the active viewing area which may be larger or more commonly smaller than the size of the buffer.

<lang csharp> static void Main(string[] args) {

   int bufferHeight = Console.BufferHeight;
   int bufferWidth = Console.BufferWidth;
   int windowHeight = Console.WindowHeight;
   int windowWidth = Console.WindowWidth;

   Console.Write("Buffer Height: ");
   Console.WriteLine(bufferHeight);
   Console.Write("Buffer Width: ");
   Console.WriteLine(bufferWidth);
   Console.Write("Window Height: ");
   Console.WriteLine(windowHeight);
   Console.Write("Window Width: ");
   Console.WriteLine(windowWidth);
   Console.ReadLine();

} </lang>

On the author's system this results in the following output:

Buffer Height: 300
Buffer Width: 80
Window Height: 25
Window Width: 80

This perfectly demonstrates that the buffer may not be the same size as the window.

COBOL

Works with: OpenCOBOL

<lang cobol> IDENTIFICATION DIVISION.

      PROGRAM-ID. terminal-dimensions.

      DATA DIVISION.
      WORKING-STORAGE SECTION.
      01  num-lines PIC 9(3).
      01  num-cols  PIC 9(3).

      SCREEN SECTION.
      01  display-screen.
          03  LINE 01 COL 01 PIC 9(3) FROM num-lines.
          03  LINE 01 COL 05 VALUE "rows by " .
          03  LINE 01 COL 13 PIC 9(3) FROM num-cols.
          03  LINE 01 COL 16 VALUE " columns.".

      PROCEDURE DIVISION.
          ACCEPT num-lines FROM LINES
          ACCEPT num-cols FROM COLUMNS

          DISPLAY display-screen

     *    This pauses the program, as ncurses will immediately revert
     *    back to the console when the program ends.
          CALL "C$SLEEP" USING BY CONTENT 3

          GOBACK
          .</lang>

Euphoria

<lang Euphoria>include graphics.e

sequence vc integer term_height, term_width

vc = video_config()

term_height = vc[VC_LINES] term_width = vc[VC_COLUMNS]

printf(1,"Terminal height is %d\n",term_height) printf(1,"Terminal width is %d\n",term_width)</lang>

F#

Translation of: C#

<lang fsharp>open System

let bufferHeight = Console.BufferHeight let bufferWidth = Console.BufferWidth let windowHeight = Console.WindowHeight let windowWidth = Console.WindowWidth

Console.Write("Buffer Height: ") Console.WriteLine(bufferHeight) Console.Write("Buffer Width: ") Console.WriteLine(bufferWidth) Console.Write("Window Height: ") Console.WriteLine(windowHeight) Console.Write("Window Width: ") Console.WriteLine(windowWidth) Console.ReadLine()</lang>

Forth

Works with: GNU Forth

Works with: SwiftForth

<lang forth>variable term-width variable term-height

s" gforth" environment? [if]

 2drop form ( height width )

[else] \ SwiftForth

 get-size ( width height ) swap

[then] term-width ! term-height !</lang>

Go

Sub-repository

Library: Go sub-repositories

<lang go>package main

import (

   "fmt"
   "os"

   "golang.org/x/crypto/ssh/terminal"

)

func main() {

   w, h, err := terminal.GetSize(int(os.Stdout.Fd()))
   if err != nil {
       fmt.Println(err)
       return
   }
   fmt.Println(h, w)

}</lang>

External command

<lang go>package main

import (

   "fmt"
   "os"
   "os/exec"

)

func main() {

   var h, w int
   cmd := exec.Command("stty", "size")
   cmd.Stdin = os.Stdin
   d, _ := cmd.Output()
   fmt.Sscan(string(d), &h, &w)
   fmt.Println(h, w)

}</lang>

Ncurses

Library: curses

<lang go>package main

import (

   "fmt"
   "log"

   "code.google.com/p/goncurses"

)

func main() {

   s, err := goncurses.Init()
   if err != nil {
       log.Fatal("init:", err)
   }
   defer goncurses.End()
   height, width := s.MaxYX()
   fmt.Println(height, width)

}</lang>

J

This is not well supported in J, but since the terminal window can be resized at any time and can have its font changed and so on, good design generally dictates that this kind of information be ignored.

Nevertheless, assuming J version 6 in its usual environment, to determine its width and height, in pixels, you can use:

<lang j>_2 {.qsmsize_jijs_</lang>

Note also that this will typically include 37 extra pixels horizontally and 79 extra pixels vertically, which are not available to display text. In other words, if the result was 700 500 you would really have 663 pixels of width and 421 pixels of height.

Julia

<lang julia> julia> using Gtk

julia> screen_size() (3840, 1080)

julia> </lang>

Kotlin

Works with: Ubuntu version 14.04

<lang scala>// version 1.1.2

/*

   I needed to execute the terminal command: 'export COLUMNS LINES'
   before running this program for it to work (returned 'null' sizes otherwise).

• /

fun main(args: Array<String>) {

   val lines = System.getenv("LINES")
   val columns = System.getenv("COLUMNS")
   println("Lines   = $lines")
   println("Columns = $columns")

}</lang>

Output:

Lines   = 24
Columns = 80

Locomotive Basic

Locomotive BASIC has no built-in command to get window dimensions, but there is a firmware call to &bb69 (TXT_GET_WINDOW) for this. So we have to use a snippet of Z80 machine code to call the firmware and copy the results from the DE and HL registers to RAM. It looks like this when disassembled:

<lang z80>4000 d5 push de 4001 e5 push hl 4002 cd 69 bb call &bb69 4005 ed 53 20 40 ld (&4020),de 4009 22 22 40 ld (&4022),hl 400c e1 pop hl 400d d1 pop de 400e c9 ret</lang>

This routine gets POKEd into RAM (starting at address &4000) and CALLed from Locomotive BASIC, then the results are retrieved with PEEK:

<lang locobasic>10 s=&4000:SYMBOL AFTER 256:MEMORY s-1 20 FOR i=0 to 14:READ a:POKE s+i,a:NEXT 30 DATA &d5,&e5,&cd,&69,&bb,&ed,&53,&20,&40,&22,&22,&40,&e1,&d1,&c9 40 CALL s 50 h=PEEK(&4020)-PEEK(&4022)+1 60 w=PEEK(&4021)-PEEK(&4023)+1 70 PRINT "window width:"; w; ", height:"; h</lang>

In practice, one would prefer to write the machine code routine as a slightly more elaborate RSX (resident system extension) which is a freely relocatable and therefore more reusable Locomotive BASIC extension. The RSX routine might be called "getwh" and accept pointers to integers, which would simplify the BASIC code to:

<lang locobasic>10 w%=0:h%=0 ' initialize and force integer type 20 |getwh,@w%,@h% ' call RSX and pass variables as pointers 30 PRINT "window width:"; w%; ", height:"; h%</lang>

Mathematica

<lang Mathematica>WIDTH=RunThrough["tput cols", ""]; HEIGHT=RunThrough["tput lines", ""];</lang>

Nim

<lang nim>import terminal

echo "Terminal width: " & $terminalWidth() echo "Terminal height: " & $terminalHeight() </lang>

OCaml

Using the library ANSITerminal in the interactive loop:

<lang ocaml>$ ocaml unix.cma -I +ANSITerminal ANSITerminal.cma

1. let width, height = ANSITerminal.size () ;;

val width : int = 126 val height : int = 47</lang>

Perl

<lang perl>use Term::Size;

($cols, $rows) = Term::Size::chars; print "The terminal has $cols columns and $rows lines\n";</lang>

Phix

The buffer is usually somewhat larger (and never smaller) than the current physical screen size. I would guess that most applications are more interested in the latter. <lang Phix>sequence vc = video_config() printf(1,"Terminal buffer height is %d\n",vc[VC_LINES]) printf(1,"Terminal buffer width is %d\n",vc[VC_COLUMNS]) printf(1,"Terminal screen height is %d\n",vc[VC_SCRNLINES]) printf(1,"Terminal screen width is %d\n",vc[VC_SCRNCOLS])</lang>

Output:

Terminal buffer height is 196
Terminal buffer width is 132
Terminal screen height is 25
Terminal screen width is 80

PicoLisp

<lang PicoLisp>(setq

  Width (in '(tput cols) (read))
  Height (in '(tput lines) (read)) )</lang>

PureBasic

PureBasic does not have native functions for reading the size of this window, but supports API-functions that allows this.

This code is for Windows only. <lang PureBasic>Macro ConsoleHandle()

 GetStdHandle_( #STD_OUTPUT_HANDLE )

EndMacro

Procedure ConsoleWidth()

 Protected CBI.CONSOLE_SCREEN_BUFFER_INFO
 Protected hConsole = ConsoleHandle()
 GetConsoleScreenBufferInfo_( hConsole, @CBI )
 ProcedureReturn CBI\srWindow\right - CBI\srWindow\left + 1

EndProcedure

Procedure ConsoleHeight()

 Protected CBI.CONSOLE_SCREEN_BUFFER_INFO
 Protected hConsole = ConsoleHandle()
 GetConsoleScreenBufferInfo_( hConsole, @CBI )
 ProcedureReturn CBI\srWindow\bottom - CBI\srWindow\top + 1

EndProcedure

If OpenConsole()

 x$=Str(ConsoleWidth())
 y$=Str(ConsoleHeight())
 PrintN("This window is "+x$+"x"+y$+ " chars.")
 ;
 Print(#CRLF$+"Press ENTER to exit"):Input()

EndIf</lang>

Python

Works with: Python version 2.6

Library: ctypes

This uses the ctypes library in order to get the console dimensions on Windows. This code is a slight refactoring of an ActiveState Recipe. For Linux, the tput utility is used.

<lang python>import os

def get_windows_terminal():

   from ctypes import windll, create_string_buffer
   h = windll.kernel32.GetStdHandle(-12)
   csbi = create_string_buffer(22)
   res = windll.kernel32.GetConsoleScreenBufferInfo(h, csbi)

   #return default size if actual size can't be determined
   if not res: return 80, 25 

   import struct
   (bufx, bufy, curx, cury, wattr, left, top, right, bottom, maxx, maxy)\
   = struct.unpack("hhhhHhhhhhh", csbi.raw)
   width = right - left + 1
   height = bottom - top + 1

   return width, height

def get_linux_terminal():

   width = os.popen('tput cols', 'r').readline()
   height = os.popen('tput lines', 'r').readline()

   return int(width), int(height)

print get_linux_terminal() if os.name == 'posix' else get_windows_terminal() </lang>

Racket

<lang racket>

1. lang racket

(require (planet neil/charterm:3:0)) (with-charterm

(charterm-screen-size))

</lang>

Raku

(formerly Perl 6) Using stty just for the heck of it. <lang perl6>my $stty = qx[stty -a]; my $lines = $stty.match(/ 'rows ' <( \d+/); my $cols = $stty.match(/ 'columns ' <( \d+/); say "$lines $cols";</lang>

Retro

This information is provided by Retro in the ch (height) and cw (width) variables. You can manually obtain it using the io ports.

<lang Retro>-3 5 out wait 5 in !cw -4 5 out wait 5 in !ch</lang>

REXX

Using TPUT under Linux/Unix

Works with: brexx

Works with: regina

Works with: rexximc

Some REXX interpreters don't provide basic terminal control as part of the language. However, it's possible to determine the size of the terminal window by using external system commands: <lang rexx>width = 'tput'( 'cols' ) height = 'tput'( 'lines' )

say 'The terminal is' width 'characters wide' say 'and has' height 'lines'</lang>

LINESIZE

The LINESIZE built-in function returns the (terminal) screen's width.   It is supported by most (classic) REXX interpreters (and some others) such as: CMS REXX, TSO REXX, VSE REXX, the IBM REXX compiler, PC/REXX, Personal REXX, REXX/imc, R4 and ROO.   A sample usage of it is: <lang rexx>width=linesize()</lang> The above example makes use of   LINESIZE   REXX program (or BIF) which is used to determine the screen width (or linesize) of the terminal (console).
The   LINESIZE.REX   REXX program is included here ──► LINESIZE.REX.

SCRSIZE

SCRSIZE is another built-in function, and returns two integers: the screen depth and the screen width.   A few classic REXX interpreters support it:   PC/REXX, Personal REXX, R4 and ROO. <lang rexx> parse value scrsize() with sd sw</lang> The above example makes use of   SCRSIZE   REXX program (of BIF) which is used to determine the screen size of the terminal (console).
The   SCRSIZE.REX   REXX program is included here ──► SCRSIZE.REX.

Ring

<lang ring> system("mode 50,20") </lang>

Ruby

<lang ruby>def winsize

 # Ruby 1.9.3 added 'io/console' to the standard library.
 require 'io/console'
 IO.console.winsize

rescue LoadError

 # This works with older Ruby, but only with systems
 # that have a tput(1) command, such as Unix clones.
 [Integer(`tput li`), Integer(`tput co`)]

end

rows, cols = winsize printf "%d rows by %d columns\n", rows, cols</lang>

Library: curses

Curses.lines and Curses.cols return the size of the terminal. The program must call Curses.init_screen, because without this call, Curses might report 0 lines and 0 columns. Beware that Curses.init_screen also switches the terminal to screen-oriented mode, and fails on those terminals that cannot support curses.

<lang ruby>require 'curses'

begin

 Curses.init_screen

 r, c = Curses.lines, Curses.cols

 Curses.setpos r / 2, 0
 Curses.addstr "#{r} rows by #{c} columns".center(c)
 Curses.getch

ensure

 Curses.close_screen

end</lang>

Scala

Works with: Ubuntu version 14.04

<lang Scala> /*

    First execute the terminal command: 'export COLUMNS LINES'
    before running this program for it to work (returned 'null' sizes otherwise).
*/

   val (lines, columns)  = (System.getenv("LINES"), System.getenv("COLUMNS"))
   println(s"Lines   = $lines, Columns = $columns")</lang>

Seed7

The functions height and width are portable and determine the dimensions of the console window. Height and width are based on terminfo respectively the Windows console API.

<lang seed7>$ include "seed7_05.s7i";

 include "console.s7i";

const proc: main is func

 local
   var text: console is STD_NULL;
 begin
   console := open(CONSOLE);
   writeln(console, "height: " <& height(console) lpad 3);
   writeln(console, "width:  " <& width(console) lpad 3);
   # Terminal windows often restore the previous
   # content, when a program is terminated. Therefore
   # the program waits until Return/Enter is pressed.
   readln;
 end func;</lang>

Sidef

Translation of: Perl 6

<lang ruby>var stty = `stty -a`; var lines = stty.match(/\brows\h+(\d+)/); var cols = stty.match(/\bcolumns\h+(\d+)/); say "#{lines} #{cols}";</lang>

Output:

24 80

Tcl

Translation of: UNIX Shell

<lang tcl>set width [exec tput cols] set height [exec tput lines] puts "The terminal is $width characters wide and has $height lines"</lang>

Alternative

Requires: GNU coreutils <lang tcl>lassign [exec stty size] width height puts "The terminal is $width characters wide and has $height lines"</lang>

UNIX Shell

Works with: Bourne Shell

<lang bash>#!/bin/sh WIDTH=`tput cols` HEIGHT=`tput lines` echo "The terminal is $WIDTH characters wide and has $HEIGHT lines."</lang>

Library: termcap

termcap is obsolete.

<lang bash>#!/bin/sh WIDTH=`tput co` HEIGHT=`tput li` echo "The terminal is $WIDTH characters wide and has $HEIGHT lines."</lang>

C Shell

<lang csh>#!/bin/csh -f set WIDTH=`tput cols` set HEIGHT=`tput lines` echo "The terminal is $WIDTH characters wide and has $HEIGHT lines."</lang>

Visual Basic

Translation of: C#

<lang vb>Module Module1

   Sub Main()
       Dim bufferHeight = Console.BufferHeight
       Dim bufferWidth = Console.BufferWidth
       Dim windowHeight = Console.WindowHeight
       Dim windowWidth = Console.WindowWidth

       Console.Write("Buffer Height: ")
       Console.WriteLine(bufferHeight)
       Console.Write("Buffer Width: ")
       Console.WriteLine(bufferWidth)
       Console.Write("Window Height: ")
       Console.WriteLine(windowHeight)
       Console.Write("Window Width: ")
       Console.WriteLine(windowWidth)
   End Sub

End Module</lang>

Output:

I put the built application in Desktop:

\Desktop>ConsoleApplication1
Buffer Height: 300
Buffer Width: 80
Window Height: 25
Window Width: 80

\Desktop>

After resizing the console:

\Desktop>ConsoleApplication1
Buffer Height: 300
Buffer Width: 80
Window Height: 14
Window Width: 49

\Desktop>

XPL0

<lang XPL0>include c:\cxpl\codes; int W, H; [W:= Peek($40, $4A); \IBM-PC BIOS data

H:= Peek($40, $84) + 1;

Text(0, "Terminal width and height = "); IntOut(0, W); ChOut(0, ^x); IntOut(0, H); ]</lang>

Output:

80x25

zkl

Unix specific solution:

Translation of: GO

<lang zkl>h,w:=System.popen("stty size","r").readln().split(); println(w," x ",h);</lang>

Output:

91 x 24