如何在bash脚本中使用sed进行更改

Question

Hi下面是我的bash脚本。它需要一个源文件和一个令牌文件，令牌文件包含servicename：用法我必须在源文件中逐行查找servicename，如果找到，然后计算内存使用量，然后用-Xmx\d{1,3}m更改-Xmxm。在下面的脚本粗线解释做什么多简单你可以先下站问题从下面的小部分脚本

line="Superviser.childOpts:-Xmx128m"
heapMB=750
line=($(echo $line|sed  "s/${-Xmx\d{1,3}m}/$-Xmx{$heapMB}m/g"))

那么上面的错误是什么

#!/bin/bash

sourceFile=$1

tokenFile=$2

if [ -z $sourceFile ]

then


    echo "Please provide a valid source file"

    exit 0


fi

    if [ -z $tokenFile ]

    then

        echo "Please provide a valid token file"

        exit 0

    fi


#read token file and tokenize with : to get service name at 0 index and percentage usages at 1

declare arr_token_name

declare arr_token_usage

count=0

while read line

do

#here line contain :percentage usages

OIFS="$IFS"

IFS=$':'

arr=($line)

IFS="$OIFS"

if [ ! -z $line ]

then

   arr_token_name[$count]=${arr[0]}

   arr_token_usage[$count]=${arr[1]}

   count=`expr $count + 1`

fi


done 
# read source file line by line test with all the tokens 

totalMemKB=$(awk '/MemTotal:/ { print $2 }' /proc/meminfo)

echo "total mem = $totalMemKB"

while read line

do

result_token_search=""

#for j in "${arr_token_name[@]}"

#do

#   echo "index=$j"

#done

count2=0

for i in "${arr_token_name[@]}"

do

#here search token in line , if found 

#calculate memory for this getting percent usage from arr_token_usage then  use calculate frmula then device by 1024

#then replace -Xmx\d{1,5}m with -Xmx

    echo "line1=$line"

    result_token_search=$(echo $line|grep -P "$i")

    if [ -n "$result_token_search"  ]

    then

        percent_usage=${arr_token_usage[$count2]}

        let heapKB=$totalMemKB*$percent_usage/100

        let heapMB=$heapKB/1024

        echo "before sed=$line"

     line=($(echo $line|sed  "s/${-Xmx\d{1,3}m}/$-Xmx{$heapMB}m/g"))

        echo "new line=$line"

        echo "token found in line $line , token = $i"

    fi

    result_token_search=""


    count2=`expr $count2+1`

    cat "$line" >> tmp.txt

done


done 

Answer 1

试试这句话：

line=$( sed  "s/-Xmx[0-9]\+/-Xmx$heapMB/" <<<$line )

用您的示例进行测试：

kent$  line="Superviser.childOpts:-Xmx128m" 

kent$  heapMB=750    

kent$  line=$( sed  "s/-Xmx[0-9]\+/-Xmx$heapMB/" <<<$line )    

kent$  echo $line
Superviser.childOpts:-Xmx750m