bash 检查目录是否不存在
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原文地址: http://stackoverflow.com/questions/41868707/
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Check if directory does not exist
提问by SLS
I have written a script to check in var/log directory, and it takes all the directories in there and checks if there is an archive directory in those directories. If an archive directory not exist, I want to create it, but once it's created the script tries to create it again.
我编写了一个脚本来检查 var/log 目录，它获取其中的所有目录并检查这些目录中是否有存档目录。如果存档目录不存在，我想创建它，但是一旦创建，脚本会尝试再次创建它。
vdir=$(sudo sh -c "find /var/log/ -maxdepth 1 -type d ! -name "archive"" )
for i in $vdir ;do
echo $i
if [[ ! -d $i/$arc ]];then
sudo sh -c "mkdir $i/$arc"
echo "$date:$HN:Creating:$i/$arc:directory" >> logrotation.log
fi
done
When I execute above code it gives me this error. Seems the script is not checking the condition.
当我执行上面的代码时，它给了我这个错误。似乎脚本没有检查条件。
mkdir: cannot create directory ‘/var/log/speech-dispatcher/archive': File exists
回答by Wes Hardaker
The issue is that you have two [symbols. You only need one:
问题是你有两个[符号。你只需要一个：
if [ ! -d $i/$arc ];then
An additional point: some shell versions don't handle the ;being right next to the closing bracket. Thus, I'd suggest formatting like this for best compatibility:
补充一点：一些 shell 版本不处理;右括号旁边的存在。因此，我建议这样格式化以获得最佳兼容性：
if [ ! -d $i/$arc ] ; then
Edit: since the above didn't help you, more thoughts:
编辑：由于以上没有帮助你，更多的想法：
It's also entirely possible that your script, running as you, can't actually read the contents of the $idirectory and thus the test will always fail (or succeed, actually). But, when you create the directory as root via sudo, it already exists.
您的脚本也完全有可能以您的身份运行，实际上无法读取$i目录的内容，因此测试总是会失败（或实际上会成功）。但是，当您通过 sudo 以 root 身份创建目录时，它已经存在。
[It would also be more efficient to run the entire script under sudo rather than just certain pieces of it.]
[在 sudo 下运行整个脚本也会更有效率，而不仅仅是其中的某些部分。]
