什么是$？在 bash 中？
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What is $? in bash?
提问by Baruch
I am trying to understand a script that was written a few years ago by someone that is no longer available here. The script references $?a few times. What is this?
我试图理解几年前由这里不再可用的人编写的脚本。该脚本引用$?了几次。这是什么？
P.S. Google couldn't help since it seems to strip the $?from the search term
PS Google 无能为力，因为它似乎$?从搜索词中删除了
回答by Basile Starynkevitch
You really should read the GNU bashmanual. $?is a special parameterwhich
你真的应该阅读GNU bash手册。$?是一种特殊的参数，其
expands to the exit status of the most recently executed foreground pipeline.
扩展到最近执行的前台管道的退出状态。
Read also the advanced bash scripting guide.
另请阅读高级 bash 脚本指南。
