Bash 脚本错误：[: 丢失]
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Bash Script error: [: missing ]
提问by Shafiq Mustapa
#!/bin/bash
if [ `date +%u` -lt 6 && `date +%H` == '19' ] ; then
echo 'Sorry, you cannot run this program today.'
else
echo 'yes, you can run today'
fi
The script above is to run a program on weekdays and every 7PM. I have check the spaces and it still return error : date.sh: 2: [: missing ]
上面的脚本是在工作日和每晚 7 点运行一个程序。我检查了空格，它仍然返回错误：date.sh: 2: [: missing ]
回答by hek2mgl
Change it to:
将其更改为：
#!/bin/bash
if [ `date +%u` -lt 6 ] && [ `date +%H` == '19' ] ; then
echo 'Sorry, you cannot run this program today.'
else
echo 'yes, you can run today'
fi
Note that the [is just a shorthand for the testcommand and ]the last argument to it. The &&operator is used like in any other command line, for example cd /home && ls
请注意，这[只是test命令及其]最后一个参数的简写。的&&运算符用于像任何其他命令行，例如cd /home && ls
回答by Cairnarvon
There are two problems with your code.
您的代码有两个问题。
The first is a simple typo: date %Hshould be date +%H.
第一个是一个简单的错字：date %H应该是date +%H。
The second is the cause of the error you're seeing: &&isn't the right operator to use. It separates commands, whereas your ifcondition should really be a single one; bash looks for ] at the end of [ `date +%u` -lt 6, doesn't find it, and errors out. You want to use -ainstead.
第二个是您所看到的错误的原因：&&使用的运算符不正确。它分隔命令，而您的if条件实际上应该是一个；bash 在 末尾查找 ] [ `date +%u` -lt 6，没有找到，并出错。你想-a改用。
