使用Bash在Linux中設置環境變數

export VAR=value 將VAR設置為value.如果需要空格，請用單引號將其括起来，例如 export VAR='my val' .如果要對變數进行插值，請使用双引號，例如 export VAR="$MY_OTHER_VAR"

人们经常建議寫作的原因

VAR=value
export VAR

而不是较短的

export VAR=value

是较长的形式比短形式在更多不同的外壳中工作.如果您知道自己正在与 bash打交道 ，当然两者都可以正常工作。

在Linux上使用Bash設置本地和環境變數

Check for a local or environment variables for a variable called LOL in Bash:

[email protected] /home/el $ set | grep LOL
[email protected] /home/el $
[email protected] /home/el $ env | grep LOL
[email protected] /home/el $

完整性檢查，没有稱為LOL的本地或環境變數。

Set a local variable called LOL in local, but not environment. So set it:

[email protected] /home/el $ LOL="so wow much code"
[email protected] /home/el $ set | grep LOL
LOL='so wow much code'
[email protected] /home/el $ env | grep LOL
[email protected] /home/el $

變數" LOL"存在於區域性變數中，但不存在於環境變數中.如果重新啟動终端，註销/登錄或執行 exec bash，則LOL將消失

Set a local variable, and then clear out all local variables in Bash

[email protected] /home/el $ LOL="so wow much code"
[email protected] /home/el $ set | grep LOL
LOL='so wow much code'
[email protected] /home/el $ exec bash
[email protected] /home/el $ set | grep LOL
[email protected] /home/el $

You could also just unset the one variable:

[email protected] /home/el $ LOL="so wow much code"
[email protected] /home/el $ set | grep LOL
LOL='so wow much code'
[email protected] /home/el $ unset LOL
[email protected] /home/el $ set | grep LOL
[email protected] /home/el $

本地變數LOL消失了。

Promote a local variable to an environment variable:

[email protected] /home/el $ DOGE="such variable"
[email protected] /home/el $ export DOGE
[email protected] /home/el $ set | grep DOGE
DOGE='such variable'
[email protected] /home/el $ env | grep DOGE
DOGE=such variable

請註意，匯出使其同時顯示為區域性變數和環境變數。

上面匯出的變數DOGE在Bash重置後仍然有效：

[email protected] /home/el $ exec bash
[email protected] /home/el $ env | grep DOGE
DOGE=such variable
[email protected] /home/el $ set | grep DOGE
DOGE='such variable'

Unset all environment variables:

您必须拔出一罐Chuck Norris才能重置所有環境變數，而無需註销/登錄：

[email protected] /home/el $ export CAN="chuck norris"
[email protected] /home/el $ env | grep CAN
CAN=chuck norris
[email protected] /home/el $ set | grep CAN
CAN='chuck norris'
[email protected] /home/el $ env -i bash
[email protected] /home/el $ set | grep CAN
[email protected] /home/el $ env | grep CAN

您建立了一个環境變數，然後重置终端以删除它们。

Or you could set and unset an environment variable manually like this:

[email protected] /home/el $ export FOO="bar"
[email protected] /home/el $ env | grep FOO
FOO=bar
[email protected] /home/el $ unset FOO
[email protected] /home/el $ env | grep FOO
[email protected] /home/el $

VAR=value 將VAR設置為值。

在那之後 也会將其提供给子程序。

export VAR 是两者的簡寫。

我认為您正在尋找 export VAR=value -尽管我可能錯了..我以前从未玩過tcsh.使用以下語法：

export