Bash 不会改变变量值
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Bash won't change variable value
提问by Mr. King
I am trying to change the variable reloadfrom 0to 1as you can see in my code below:
我正在尝试将变量reload从更改为0，1如下面的代码所示：
for d in /home/*; do
u="${d##*/}";
reload=0;
echo "Checking $u";
if [ -e /home/$u/info/reload.php ]; then
echo "FOUND!";
reload=1;
fi
done
echo $reload;
if [ $reload = 1 ]; then
service apache2 reload
fi
The problem is that it doesn't get changed, $reloadremains as 0, the output is similar to this (apache does not get reloaded):
问题是它没有改变，$reload仍然是0，输出与此类似（apache不会重新加载）：
Checking user1
FOUND!
Checking user2
0 #< this should be 1 not 0 :(
Why won't my bash variable change??
为什么我的 bash 变量不会改变？
回答by Johnsyweb
You're resetting reloadfor each user. If the file is not found for the last user, reloadwill be 0when you exit the loop.
您正在reload为每个用户重置。如果没有找到最后一个用户的文件，reload将0在您退出循环时出现。
Suggested fixes (with indentation for readability):
建议的修复（带有缩进以提高可读性）：
#!/usr/bin/env bash
reload=0
for d in /home/*; do
u="${d##*/}"
echo "Checking $u";
if [ -e /home/$u/info/reload.php ]; then
echo "FOUND!"
reload=1
fi
done
echo $reload
if [ $reload -eq 1 ]; then
service apache2 reload
fi
