bash 错误：Shell 脚本返回一元运算符是预期的错误消息
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Error : Shell script returns unary operator is expected error message
提问by KItis
i am fixing a given shell script and i am getting following error message
我正在修复给定的 shell 脚本，但收到以下错误消息
line 322: [: ==: unary operator expected
this error is returned from this line.
这个错误是从这一行返回的。
if [ == "managed?.out" ];then
could someone explain me what makes this error
有人可以解释一下是什么导致了这个错误
Also could someone explain what is the purpose of using ? in the"managed?.out"
也有人可以解释使用的目的是什么？在“托管？.out”中
thanks in advance for any help
提前感谢您的帮助
回答by codaddict
You need to quote $4:
您需要引用$4：
if [ "" == "managed?.out" ];then
回答by Raphael Roth
change the if statement to
将 if 语句更改为
if [ "" == "managed?.out" ];then
The double-quotes are only necessary as you use $4, if your variable would be $string, you would not need them.
只有在使用 $4 时才需要双引号，如果变量是 $string，则不需要它们。
should "?" be interpreted as a bash-wildcard? if yes, you need to use
应该 ”？” 被解释为 bash 通配符？如果是，您需要使用
if [[ "" == managed?.out ]];then
回答by chemila
try:
尝试：
if [[ == "managed?.out" ]];then
