shell脚本修改配置文件指定行的值

<Data Count="6">
<Line>
<switch>
</switch>
<description>Version</description>
<value>1</value>
</Line>
<Line>
<switch>
</switch>
<description>ExpireTime</description>
<value>300</value>
</Line>
<Line>
<switch>
</switch>
<description>MaxProcessTime</description>
<value>15</value>
</Line>
<Line>
<switch>
</switch>
<description>MaxQueueSize</description>
<value>2000</value>
</Line>
<Line>
<switch>
</switch>
<description>MaxStatisticsTime</description>
<value>1000000</value>
</Line>
<Line>
<switch>
</switch>
<description>StatisticsCount</description>
<value>10</value>
</Line>
</Data>

#!/bin/bash

file_name="config.xml"
key_value="MaxStatisticsTime"

changeFile()
{
declare -i nline
getline()
{
cat -n $file_name|grep "${key_value}"|awk '{print $1}'
}
getlinenum()
{
awk "BEGIN{a=`getline`;b="1";c=(a+b);print c}";
}
nline=`getlinenum`
sed -i "${nline}s/>[^)]*</>$1</g" $file_name
}

changeFile 2000000