有沒有辦法清除使用source <（grep = ...）讀取的變量？

Question

這是可能與source <(grep = test.ini)讀取來自.ini文件變量：

$ cat test.ini 
[head] 
    shoulders=/hahaha/ 
    knees=/lololol/ 
    toes=/kekeke/ 

$ source <(grep = test.ini) 

$ echo $shoulders 
/hahaha/ 

$ echo $knees 
/lololol/ 

$ echo $toes 
/kekeke/ 

我可以從source <(grep = ...)命令，例如讀手動清除變量

$ unset toes 
$ echo toes 

但是，有沒有辦法自動跟蹤哪些變量從source命令添加和取消設置它們放在一起？

Answer 1

unset $(awk -F\= '/=/ { printf gensub(" ","","g",$1)" " }' test.ini) 

用awk創建變量的列表中設置，然後使用該輸出來運行未設置。我們使用gensub來擺脫被設置的變量周圍的空間。

Answer 2

通常，這種事情是非常不可靠的。但是，你可以這樣做：

set | grep -v ^_ > /tmp/original-vars # record variables 
source <(grep = test.ini)    # read from init file 

# now, compare current variables assigned with the original and unset 
# those that were not originally assigned while attempting 
# to mask out some common internal variables that bash sets but making 
# no claims at robustness or safety: 
set | grep -v ^_ | diff -u - /tmp/original-vars \ 
    | awk '/^-/ && NR>1{print $2}' FS=[=-] \ 
    | while read var; do unset $var; done 

因人而異，讀者要注意，等