Use awk to match a word, then find the first occurrence of another word

I am trying to find a way to re-search for another matching word after I already had a match.

I am specifically trying to get the brightness value of one of my monitors. For example a part of the output of my xrandr --verbose is the following:

DP-1 connected 1920x1080+1920+0 (0x6e) normal (normal left inverted right x axis y axis) 598mm x 336mm
    Identifier: 0x46
    Timestamp:  73906594
    Subpixel:   horizontal rgb
    Gamma:      1.0:1.0:1.0
    Brightness: 1.0
    Clones:    
    CRTC:       1

I want to look for the word connected and then get the first occurrence of the word Brightness.

What I have tried which works is the following:

xrandr --verbose | awk '/ connected /{print $1}/Brightness:/{print $2}'

Which gives me the following output, because I have two monitors:

But assuming I only want the first occurrence for a result I have tried this:

 xrandr --verbose | awk '/LVDS-1/{getline; getline; getline; getline; getline; print$0}'

Which works as intended giving me the value of brightness for this specific monitor.

But I am not sure whether the Brightness value is always on 5 lines later. So I was looking for a more robust solution.

Answer

awk solution:

xrandr --verbose | awk '/LVDS-1/{f=1}/Brightness:/ && f{print $2; exit}'

/LVDS-1/{f=1} – on encountering line with needed LVDS-1 set flag f=1
/Brightness:/ && f – when encountering the closest line with Brightness: and active flag f (for LVDS-1) – print the value and exit the script execution immediately (to avoid redundant iterations)

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Answer