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2

How to append string before and after a line using sed

rated 0 times [ 2] [ 0] / answers: 1 / hits: 6596 / 2 Years ago, sun, january 16, 2022, 12:34:24

I have lines form a command output as given below.

service:clus1-svr          clus1-node2                      started    [Z]

service:clus1-svr          clus1-node2                      started

I want to add string before and after the line which indicate [Z] only. So the result may come as:

<font>service:clus1-svr          clus1-node2                      started    [Z]</font>

Can anyone please help me to do this. Your help greatly appreciated.

i tried below, but that changes all the line from the output

sed -i "s/.*/<font color="red">&</font>/"

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amacal

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3 Years ago

answered 2 Years ago panshow · Accepted Answer

You were pretty close with your attempt; all you needed to do was to narrow down the execution of the substitution only to lines containing [Z] at the end:

sed -i '/[Z]$/ s/.*/<font>&</font>/' infile

However, here's another awk solution:

awk '$4=="[Z]" {printf("%s%s%s

", "<font>", $0, "</font>"); next} {print}' infile

$4=="[Z]": pattern; if the 4th field of the currently processed record is [Z], executes the following action; otherwise, it skips to the next pattern / action;

printf("%s%s%s ", "<font>", $0, "</font>"): prints <font>, the currently processed record and </font> as strings followed by a newline;

next: skips to the next record;

print: prints the currently processed record followed by a newline;

Sample output:

user@debian ~ % cat infile

service:clus1-svr          clus1-node2                      started    [Z]

service:clus1-svr          clus1-node2                      started

user@debian ~ % awk '$4=="[Z]" {printf("%s%s%s

", "<font>", $0, "</font>"); next} {print}' infile

<font>service:clus1-svr          clus1-node2                      started    [Z]</font>

service:clus1-svr          clus1-node2                      started