Есть файл конфигурации my.conf:
[Значения]
res_fix="xrandr -s 1440x900"
Ncomp="20"
Height="900"
Width="1440"
РЕШЕНО.
#!/bin/bash
cd path_to/my.conf
source my.conf
Height=$(xrandr --current | grep '*' | uniq | awk '{print $1}' | cut -d 'x' -f2)
Width=$(xrandr --current | grep '*' | uniq | awk '{print $1}' | cut -d 'x' -f1)
sed -i "s/^Height.*/Height=\"$Height\"/g" my.conf
sed -i "s/^Width.*/Width=\"$Width\"/g" my.conf
#slavaisu
