简单的 BASH 如果其他
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easy BASH If Else
提问by jmituzas
Ok I cant get this to work for some reason
好的，由于某种原因，我无法使其正常工作
if /etc/mysql/my.cfn exist
then goto end;
else bash install.sh;
end exit;;
Thanks in advance, Joe
提前致谢，乔
回答by SiegeX
Check for non-existence and run install.shif true.
检查不存在，install.sh如果为真则运行。
[[ ! -e /etc/mysql/my.cfn ]] && bash install.sh
回答by Gordon Davisson
Here's a relatively literal translation:
这是一个比较直白的翻译：
if [ -e /etc/mysql/my.cfn ]; then
exit # Note: bash does not have a goto command
else
bash install.sh
fi
Or, eliminate the irrelevant then condition, and invert the test:
或者，消除不相关的 then 条件，并反转测试：
if [ ! -e /etc/mysql/my.cfn ]; then
bash install.sh
fi
回答by glenn Hymanman
The :command in bash with no arguments is a no-op, so you can use that in an if-body if you need to do nothing.
:bash 中没有参数的命令是无操作的，所以如果你什么都不用做，你可以在 if-body 中使用它。
if something; then
:
else
do something else
fi
Of course, you'd normally want to write that as:
当然，您通常希望将其写为：
if ! something; then
do something else
fi
or
或者
something || do something else
回答by lecodesportif
Your four lines in one line of Bash:
一行 Bash 中的四行：
[[ -e /etc/mysql/my.cfn ]] && exit || bash install.sh
Did you mean my.cnf?
你是说我的吗？cnf?
回答by 0xC0000022L
(One) correct syntax is:
（一）正确的语法是：
if [[ expression ]]; then
command
else
command
fi
The traditional style would be:
传统风格是：
if test -f filename; then
command
fi
