31

I'm looking for a method of reporting display resolution. I want to set up scripts to launch rdesktop, and I want to launch it on several machines with different resolutions, so I want a way to dynamically determine it.

37

Use the command xrandr. Without any argument it displays the available resolutions and the current one (with an asterisk), for instance:

$ xrandr | fgrep '*'
  • Could you append some sample output to the answer? And I'm guessing xrandr |g grep \* does the trick? – Ehtesh Choudhury Apr 26 '13 at 19:38
11

Alternative solution: xdpyinfo | grep dimensions. xdpyinfo is older than xrandr, so might be more portable if you happen to use a very old distribution or some different X server.

  • 2
    Indeed, but some (all ?) multi-monitor setups appear as one screen in xdpyinfo while xrandr correctly enumerates screens and their resolution. This may or may not be a problem depending on the context. – Stéphane Gourichon May 7 '15 at 14:51
  • Note: while xdpyinfo seems to report correct dimensions in pixels, it reports wrong resolution (DPI). E.g. on my monitor with dimesions 3840x2160 (native and actual) and size 708mm x 399mm as reported by xrandr, xdpyinfo says that resolution is 96x96 dots per inch. – Ruslan Sep 3 '18 at 14:03
6

You can get the horizontal and vertical resolutions using the following command:

xdpyinfo | grep dimensions | awk '{print $2}' | awk -Fx '{print $1, $2}'

or, in more compact form (as suggested by Peter.O in this comment):

xdpyinfo | awk -F'[ x]+' '/dimensions:/{print $3, $4}' 

For exmaple, on a 1600x900 display this will produce the following output:

1600 900

You can then place the values into separate variables using the command:

read RES_X RES_Y <<<$(xdpyinfo | awk -F'[ x]+' '/dimensions:/{print $3, $4}')

Display the values of the above variables using the command:

echo $RES_X, $RES_Y

On a 1600x900 display, the output is:

1600, 900
  • 1
    xdpyinfo | awk -F'[ x]+' '/dimensions:/{print $3, $4}' – Peter.O Apr 13 '15 at 15:29
  • @Peter.O, thanks. This is a nice compact form of the command. I've updated the answer. – crayzeewulf Apr 13 '15 at 21:16
  • Indeed, but some (all ?) multi-monitor setups appear as one screen in xdpyinfo while xrandr correctly enumerates screens and their resolution. This may or may not be a problem depending on the context. – Stéphane Gourichon May 7 '15 at 14:52
5

I should have looked a little harder before posting. xrandr will echo the current display settings, if not given any other arguments.

By default, this will dump all possible display settings, this can be filtered as follows:

xrandr | egrep '^[^ ]|[0-9]\*\+'
1

Clean xrandr output for imagemagick use

xrandr |grep \* |awk '{print $1}'

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.