Bash 比较输出而不是命令
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Bash compare output rather than command
提问by moztech
Trying to create a script to read a remote file and check the md5 checksum and alert if a mismatch yet getting an error I can't understand.
尝试创建一个脚本来读取远程文件并检查 md5 校验和，并在不匹配时发出警报，但我无法理解。
#!/bin/sh
REMOTEMD5=$(ssh user@host 'md5sum file.txt')
LOCALMD5=$(md5sum 'file.txt')
if [$LOCALMD5 !== $REMOTEMD5]
then
echo "all OK"
else
echo -e "no match, Local:"$LOCALMD5"\nRemote:"$REMOTEMD5
fi
This returns line 4: [6135222a12f06b2dfce6a5c1b736891e: command not found
这返回 line 4: [6135222a12f06b2dfce6a5c1b736891e: command not found
I've tried using ' or " around the $LOCALMD5 but never seem able to get this to compare the outputs. What am I doing wrong? Thanks
我试过在 $LOCALMD5 周围使用 ' 或 " 但似乎永远无法得到它来比较输出。我做错了什么？谢谢
回答by Joachim Isaksson
Try;
尝试;
if [ "$LOCALMD5" == "$REMOTEMD5" ]
which should work better.
哪个应该工作得更好。
Edit: I think you got == and != reversed in your code.
编辑：我认为你的代码中 == 和 != 颠倒了。
回答by Mithrandir
I think it should be like this:
我觉得应该是这样的：
#!/bin/sh
REMOTEMD5=$(ssh user@host 'md5sum file.txt')
LOCALMD5=$(md5sum 'file.txt')
if [ "$LOCALMD5" == "$REMOTEMD5" ]
then
echo "all OK"
else
echo -e "no match, Local:"$LOCALMD5"\nRemote:"$REMOTEMD5
fi
The space between the bracket and the value is important!
括号和值之间的空格很重要！
回答by Kyle Jones
[isn't bash syntax, it is a command. So you must have a space between it and its first argument $LOCALMD5. There also needs to be a space between $REMOTEMD5and ].
[不是 bash 语法，它是一个命令。所以你必须在它和它的第一个参数之间有一个空格$LOCALMD5。$REMOTEMD5和之间也需要有一个空格]。
