sed - comment a matching line and x lines after it
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I need help with using sed to comment a matching lines and 4 lines which follows it.
in a text file.

my text file is like this:

    [myprocess-a]
    property1=1
    property2=2
    property3=3
    property4=4
    
    [anotherprocess-b]
    property1=gffgg
    property3=gjdl
    property2=red
    property4=djfjf
    
    [myprocess-b]
    property1=1
    property4=4
    property2=2
    property3=3

I want to prefix # to all the lines having text '[myprocess' and 4 lines that follows it
expected output:

    #[myprocess-a]
    #property1=1
    #property2=2
    #property3=3
    #property4=4
    
    [anotherprocess-b]
    property1=gffgg
    property3=gjdl
    property2=red
    property4=djfjf
    
    #[myprocess-b]
    #property1=1
    #property4=4
    #property2=2
    #property3=3

Greatly appreciate your help on this.



