


The key to setting a permanent environment variable is to select the right configuration file or system settings. 1. Linux/macOS users need to edit the corresponding files according to the scope of use, such as ~/.bashrc or /etc/environment, and use the source command to take effect; 2. Windows users modify it through "Advanced System Settings", pay attention to the difference between the system and user variables; 3. Avoid format errors when modifying PATH and restart the terminal to ensure it takes effect. As long as the operation is accurate, setting permanent environment variables is not complicated.
Setting permanent environment variables is not difficult, but many people will get stuck in specific operation steps. The key is to figure out which system you want to set it up, which users you want to take effect, and how to modify the configuration file.
Understand the scope of application of environment variables
Different systems and users have different configuration files, and it will be in vain to get the wrong location. Environment variables for Linux and macOS are usually managed through shell configuration files, such as .bashrc
, .bash_profile
, or .zshrc
, while Windows is set through system properties.
- If you only add a variable to yourself, changing
~/.bashrc
or~/.zshrc
is enough - If it is a variable that all users want to use, you have to use
/etc/profile
or/etc/environment
- Desktop version of Linux may also require editing
~/.pam_environment
to take effect globally
How to modify Linux/macOS environment variables
Open the terminal and find the configuration file that your shell uses. You can use echo $SHELL
to confirm whether you are currently using bash or zsh, and then edit the corresponding file.
Take bash as an example:
- Enter
nano ~/.bashrc
to open the configuration file - Add
export YOUR_VAR=value
at the end of the file - Save and exit, enter
source ~/.bashrc
to make the changes take effect immediately
If you want all users to use this variable, write this line into /etc/environment
, the format is YOUR_VAR=value
, and no export
is required.
Note: Some distributions (such as Ubuntu) do not allow other variables in
/etc/environment
, so don't write content likePATH=$PATH:/your/path
here, as there will be problems.
How to set it more securely on Windows?
The way Windows sets permanent variables is relatively simple, but it is also easy to ignore some details. Right-click "This Computer" → Properties → Advanced System Settings → Environment Variables to add or modify changes.
But there are a few things to note:
- System variables are for all users, and user variables are only effective for your current account.
- When modifying PATH, it is recommended to use the "Edit" button instead of pasting directly to avoid format errors.
- The new variable will be read only by the newly opened command line window, and the old cmd/powershell may still be the old value.
Sometimes the settings do not take effect, but in fact, it is caused by not restarting the terminal or graphical interface application.
Basically that's it. As long as you select the right configuration file or setting location, it can be done at once in most cases.
The above is the detailed content of How to set environment variables permanently. For more information, please follow other related articles on the PHP Chinese website!

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