How do I find out my screen resolution from a shell script?

Question

How do I find out my screen resolution from a shell script?

Solution 1

xdpyinfo | grep dimensions will give you the total resolution, if you have multiple monitors it will be the sum of all of them. xrandr --current will give you the resolution for each monitor.

I use this snippet to find the maximum possible resolution for rDesktop without going to full screen:

Xaxis=$(xrandr --current | grep '*' | uniq | awk '{print $1}' | cut -d 'x' -f1)

Yaxis=$(xrandr --current | grep '*' | uniq | awk '{print $1}' | cut -d 'x' -f2)

Output:

Xaxis = 1280
Yaxis = 1024

Minus windows decoration (more or less):

MaxRes=$(($Xaxis-5))"x"$(($Yaxis-25))

Output:

MaxRes = 1275x999

Which is the max resolution for rDesktop without going full screen.

End command:

rdesktop -u $User -P -z -5 -g $MaxRes $Host &

It works fine so far but I haven't tested thoroughly though.

Another example is for screencast with avconv:

avconv -f x11grab -r 15 -s `xrandr --current | grep  '*' | uniq | awk '{print $1}'` -i :0.0 -c:v libx264 ./output.mp4

Solution 2

You could use the xrandr -q command. From that you can create a shell script if needed.

For more information on the command go here or type man xrandr

Solution 3

A very simple method is to read out the modes file in the sys-directory:

cat /sys/class/graphics/*/modes

or respectively

cat /sys/class/graphics/*/virtual_size

Solution 4

Reading the Monitor Screen Data

The vesa standard provides a method of how to read the monitor screen resolution.

Extended Display Identification Data (EDID): This standard defines data formats to carry configuration information, allowing optimum use of displays.

A monitor typically supports multiple resolutions and refreshrates. Of course someone will prefer the maximum (physical) one.

To read this monitor data, try one of these solutions:

• edid-decode

  If not installed, type

  sudo apt install edid-decode
  

  Then read the edid file

  edid-decode /sys/class/drm/card0-eDP-1/edid
  

• read-edid

  Install with

  sudo apt install read-edid 
  

  Then read via i2c the screen monitor data and parse it

  sudo get-edid | parse-edid
  

• Hexdump the edid data

  In case edid-tools are not installed, you can dump the edid hex-file, e.g.:

  hd /sys/class/drm/card0-eDP-1/edid
  

  To encrypt this hex file take a look at wiki or download the edid specifications.

Solution 5

xdpyinfo will do it, with some parsing. It gives a lot of info which you'll then have to dig the screen number, and dimensions from

View more solutions

Comments

[To Kra]

it says> xdpyinfo: Unable to open display "".

[CMCDragonkai]

How do you find out the available modes to change to?

[c24w]

If you don't need to subtract for window decoration (etc), you can do this in a one-liner rdesktop [other_args] -g $(xrandr --current | grep '*' | uniq | awk '{print $1}').

[Scott - Слава Україні]

Is there any reason for somebody to use these commands instead of the ones in Eliezer E. Vargas’s answer?

[Scott - Слава Україні]

Please edit that information into your answer.

[Dennis Williamson]

It's not the sum for multiple monitors. It's the dimensions of a bounding box which contains all the monitors.

[SapuSeven]

xrandr --current | grep '*' | awk -v line="$SCREEN" 'NR==line{print $1}' | cut -d 'x' -f1 if you want to specify a screen (with a multi-monitor setup) (SCREEN is 1-indexed)

[UlfR]

If you dont have X and xrandr installed, edid-decode is a perfect tool when you want to know the supported resolutions of the connected monitor!

[Admin]

I think this is the best answer for linux.