永久未设置环境变量SUMO_HOME

Question

以前，我通过在/etc/ SUMO_HOME中添加SUMO_HOME='/usr/share/ sumo‘来安装sumo和设置环境变量SUMO_HOME。

现在我已经卸载了sumo并希望取消env SUMO_HOME，我尝试了以下操作：

1. $ unset SUMO_HOME
2. https://askubuntu.com/a/624958/645099

与第二点一样，我打开了这些文件：

/etc/environment
/etc/profile
~/.profile
~/.bashrc

我在这些文件中搜索SUMO_HOME。正如前面添加的那样，我在/etc/环境中找到了它，删除了该行，重新启动了系统。

但是，如果我键入：$ echo $SUMO_HOME

我得到输出: /usr/share/sumo

我如何永久取消它的价值？

我的命令和输出：

1. 检查sumo路径和SUMO_HOME env。变量

$ whereis sumo
sumo: /usr/bin/sumo /usr/share/sumo /usr/share/man/man1/sumo.1.gz

$ echo $SUMO_HOME
/usr/share/sumo

1. 移除相扑

$sudo apt-get remove sumo

Reading package lists... Done
Building dependency tree       
Reading state information... Done
The following packages were automatically installed and are no longer required:
  libmono-addins-gui0.2-cil libmono-addins0.2-cil libmono-posix4.0-cil
  libmono-sharpzip4.84-cil libmono-system-core4.0-cil
Use 'sudo apt autoremove' to remove them.
The following packages will be REMOVED:
  sumo
0 upgraded, 0 newly installed, 1 to remove and 390 not upgraded.
After this operation, 53.0 MB disk space will be freed.
Do you want to continue? [Y/n] y
(Reading database ... 233311 files and directories currently installed.)
Removing sumo (1.3.1+dfsg1-7) ...
Processing triggers for mime-support (3.60ubuntu1) ...
Processing triggers for desktop-file-utils (0.23-1ubuntu3.18.04.1) ...
Processing triggers for man-db (2.8.3-2) ...
Processing triggers for gnome-menus (3.13.3-11ubuntu1) ...

1. 再次检查sumo路径和SUMO_HOME env。变量

$ whereis sumo
sumo: /usr/share/sumo

$echo $SUMO_HOME 
/usr/share/sumo

1. 未设置SUMO_HOME

$ unset SUMO_HOME

$ echo $SUMO_HOME 
No outpout

1. 再启动系统
2. 再次检查sumo路径和SUMO_HOME env。变量

$ whereis sumo
sumo: /usr/share/sumo

$echo $SUMO_HOME 
/usr/share/sumo

为什么它仍然表现得一样？

Answer 1

在喝咖啡之前，运行以下命令：

sudo time grep -rnw --exclude-dir={media,mnt,proc,root,run,sys,/tmp,tmpfs,var} '/' -e "SUMO_HOME"

它将搜索整个分区，以查找所有文件中出现的所有SUMO_HOME。它省略了其他驱动器/分区(mnt)和临时系统目录中的文件。

在HDD上，命令将花费最长的时间，但是对于一个带有20 GB文件的SSD，它需要3分钟：

$ sudo time grep -rnw --exclude-dir={media,mnt,proc,root,run,sys,/tmp,tmpfs,var} '/' -e "SUMO_HOME"
[sudo] password for rick:          
Binary file /home/rick/.mozilla/firefox/9fu0cuql.default/places.sqlite matches
Binary file /home/rick/.mozilla/firefox/9fu0cuql.default/sessionstore-backups/recovery.jsonlz4 matches
Binary file /home/rick/.mozilla/firefox/9fu0cuql.default/sessionstore-backups/recovery.baklz4 matches
Binary file /home/rick/.mozilla/firefox/9fu0cuql.default/places.sqlite-wal matches
Binary file /home/rick/.cache/mozilla/firefox/9fu0cuql.default/cache2/entries/E883FF0A3B2BE2423996DA9A152C6B85AD52385C matches
53.23user 19.36system 2:09.36elapsed 56%CPU (0avgtext+0avgdata 19632maxresident)k
46678523inputs+0outputs (0major+7578minor)pagefaults 0swaps

忽略在此问题中键入的浏览器中出现的条目，并回答线程。上面.cache中的单个条目并不重要，但是您可能有其他重要的条目。