variables - sed 增量号

Question

我想用增量值替换一些文本。
考虑文件 xx:

<outro>dfdfd</outro>
<RecordID>1</RecordID>
<outro>dfdfd</outro>
<RecordID>1</RecordID>
<outro>dfdfd</outro>
<RecordID>1</RecordID>
<outro>dfdfd</outro>

和 sed 命令:

for n in seq 3;do sed -e 's/<RecordID>\d/<RecordID>'`echo $n`'/' xx; done

echo $n命令不会增加。

也试过:

n=1; sed -e 's/<RecordID>/<RecordID>'`echo $n ;let n=$n+1`'/g' xx

但没有成功。

仅考虑 sed(无 awk 或 perl)如何使 RecordID 字段递增，如下所示:

<outro>dfdfd</outro>
<RecordID>1</RecordID>
<outro>dfdfd</outro>
<RecordID>2</RecordID>
<outro>dfdfd</outro>
<RecordID>3</RecordID>
<outro>dfdfd</outro>

Answer 1

while read line; do n=$((++n)) &&  echo $line|sed -e 's/[0-9]/'$(($n))'/' ; done < patt