root PATH的腳本在重新啓動後發生改變並永久反映

Question

我有一個腳本，它執行一些基本的PATH完整性檢查，並在~/.bash_profile中輸入一行以獲取我的腳本，以便在根目錄PATH中對腳本所做的更改是永久的跨重啓：

cat path_clean 
#!/bin/bash 

OLD_PATH=`echo $PATH` 

OIFS=$IFS 
IFS=: 
for path in ${OLD_PATH}; do 
    [ -d "${path}" ] || continue 
    paths=("${paths[@]}" "${path}") 
done 

while read -r stat owner path; do 
    [ "${owner}${stat:5:1}${stat:8:1}" = 'root--' ] || continue 
    newpath="${newpath}:${path}" 
done < <(stat -c "%A:%U:%n" "${paths[@]}" 2>/dev/null) 

IFS=${OIFS} 

NEW_PATH=${newpath#:} 
export PATH=${NEW_PATH} 
egrep "^[ ]*if.*fi;" ~/.bash_profile &> /dev/null 
if [ $? -ne 0 ]; 
then 
    echo 'if [ -f /root/path_clean ]; then source /root/path_clean; fi;' >>  ~/.bash_profile 
fi 

一切運行正常，當我運行該腳本第一次是這樣的：

./path_clean 
. ~/.bash_profile 

但腳本有一個問題。如果我多次執行. ~/.bash_profile，那麼我會看到PATH變量中的值每次重複一次。

例如腳本執行之前我PATH是：

[root@labeir1 ~]# echo $PATH 
    /usr/bin/X11:/usr/kerberos/sbin:/usr/kerberos/bin:/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/opt/ulticom/diameter/bin:/apps/omni/bin 

現在運行. ~/.bash_profile後第一時間，一切正常：

[root@labeir1 ~]# ./path_clean 
[root@labeir1 ~]# echo $PATH <--still same as original `PATH`, which is ok 
    /usr/bin/X11:/usr/kerberos/sbin:/usr/kerberos/bin:/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/opt/ulticom/diameter/bin:/apps/omni/bin:/root/bin 
[root@labeir1 ~]# . ~/.bash_profile <--now sourcing `.bash_profile`1st time 
[root@labeir1 ~]# echo $PATH <--my script has changed `PATH` fine. 
/usr/kerberos/sbin:/usr/kerberos/bin:/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/opt/ulticom/diameter/bin:/apps/omni/bin 
[root@labeir1 ~]# . ~/.bash_profile 
[root@labeir1 ~]# echo $PATH <-- problem starts 
    /usr/kerberos/sbin:/usr/kerberos/bin:/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/opt/ulticom/diameter/bin:/apps/omni/bin:/usr/kerberos/sbin:/usr/kerberos/bin:/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/opt/ulticom/diameter/bin:/apps/omni/bin:/usr/kerberos/sbin:/usr/kerberos/bin:/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/opt/ulticom/diameter/bin:/apps/omni/bin 
[root@labeir1 ~]# . ~/.bash_profile 
[root@labeir1 ~]# echo $PATH 
/usr/kerberos/sbin:/usr/kerberos/bin:/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/opt/ulticom/diameter/bin:/apps/omni/bin:/usr/kerberos/sbin:/usr/kerberos/bin:/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/opt/ulticom/diameter/bin:/apps/omni/bin:/usr/kerberos/sbin:/usr/kerberos/bin:/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/opt/ulticom/diameter/bin:/apps/omni/bin:/usr/kerberos/sbin:/usr/kerberos/bin:/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/opt/ulticom/diameter/bin:/apps/omni/bin:/usr/kerberos/sbin:/usr/kerberos/bin:/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/opt/ulticom/diameter/bin:/apps/omni/bin:/usr/kerberos/sbin:/usr/kerberos/bin:/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/opt/ulticom/diameter/bin:/apps/omni/bin:/usr/kerberos/sbin:/usr/kerberos/bin:/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/opt/ulticom/diameter/bin:/apps/omni/bin:/usr/kerberos/sbin:/usr/kerberos/bin:/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/opt/ulticom/diameter/bin:/apps/omni/bin 

請建議什麼樣的變化，使腳本，以便使其工作正常並根除這個問題。

Answer 1

我的猜測是，在使用之前你需要清除newpath。否則，它將保留最後一個source命令剩下的值。