How to update the PATH user environment variable from command-line

Question

I have a system PATH variable with the system level config. I use the user PATH variable to complement the PATH with user-specific config.

I would like to update the user PATH variable from command-line for example with setx.

But I don't know how to reference the existing user path in setx.

In the following command (setx without /M)

setx PATH c:\my-user-specifc-bin-path;%PATH%

the first PATH means user PATH but the second %PATH% will be substituted by the "full" (user + system) PATH.

So it means that the entire system path would be duplicated in the user PATH... what is definitively not what I want.

I would like to:

• Affect only the user PATH environment variable
• Append/Prepend one or more path element to the existing value
• Do it from the command-line.

Solution 1

PowerShell version, set PATH for user:

1. Set new PATH (overwrite) for current user:

PS> Set-ItemProperty -path HKCU:\Environment\ -Name Path -Value "C:\MyPath1"

2. Set append to current user PATH:

PS> Set-ItemProperty -path HKCU:\Environment\ -Name Path -Value "$((Get-ItemProperty -path HKCU:\Environment\ -Name Path).Path);C:\MyPath1"

3. Set prepend to current user PATH:

PS> Set-ItemProperty -path HKCU:\Environment\ -Name Path -Value "C:\MyPath1;$((Get-ItemProperty -path HKCU:\Environment\ -Name Path).Path)"

Solution 2

To set the User PATH overwriting any previous value:

setx PATH "C:\MyPath1"

To prepend a value "C:\MyPath0" to the existing User PATH:

for /f "skip=2 tokens=3*" %a in ('reg query HKCU\Environment /v PATH') do @if [%b]==[] ( @setx PATH "C:\MyPath0;%~a" ) else ( @setx PATH "C:\MyPath0;%~a %~b" )

To append a value "C:\MyPath2" to the existing User PATH:

for /f "skip=2 tokens=3*" %a in ('reg query HKCU\Environment /v PATH') do @if [%b]==[] ( @setx PATH "%~a;C:\MyPath2" ) else ( @setx PATH "%~a %~b;C:\MyPath2" )

The if-else condition is required because the User PATH may or may not contain spaces. If you want you can save the commands as generic batch files (be sure to double each % sign) that accept the value to be set/prepended/appended as an argument.

Batch File

:: PATH-ADD - add a path to user path environment variable

@echo off
setlocal

:: set user path
set ok=0
for /f "skip=2 tokens=3*" %%a in ('reg query HKCU\Environment /v PATH') do if [%%b]==[] ( setx PATH "%%~a;%1" && set ok=1 ) else ( setx PATH "%%~a %%~b;%1" && set ok=1 )
if "%ok%" == "0" setx PATH "%1"

:end
endlocal
echo.

Solution 3

need SETX /M, default SETX set to HKEY_CURRENT_USER

SETX /M PATH c:\my-bin-path;%PATH%

Solution 4

This seems to work:

setx PATH "c:\my-user-specifc-bin-path-which-may-contain-spaces;"%%PATH%%

View more solutions

Comments

[Tutu]

This affect the system PATH variable... maybe my example was misleanding, but I wold like to update the user PATH variable specifically.

[STTR]

@Chris op111.net/82

[nowox]

Unfortunately it doesn't work if the user PATH is not already defined :(

[Karan]

@KJK: for /? will tell you all you need to know. :) I didn't want to replicate it all here unnecessarily and thought that info would be easy to figure out anyway.

[Mofi]

The code does not check if user PATH already ends with a semicolon in which case appending passed directory should be done without an additional semicolon. But the biggest problem with this code is a corruption of user PATH if the string becomes longer than 1024 characters because of setx truncates the string to 1024 characters with displaying an appropriate information before adding it to Windows registry. So it could happen that instead of appending passed directory, the existing user PATH is truncated (garbled) by this code.

[Mofi]

It is an absolute NO GO, NEVER EVER to update user or system PATH using local PATH. This command line really corrupts user PATH by adding to Windows registry for user PATH the string c:\my-user-specifc-bin-path-which-may-contain-spaces;%C:\Win‌​dows\System32;C:\Win‌​dows;C:\Windows\Syst‌​em32\wbem;C:\Windows‌​\System32\WindowsPow‌​erShell\v1.0\;% in best case. Everyone using this command line has successfully corrupted the user PATH setting and so local PATH as used by all processes running with current user account after Windows restart or logoff/ logon.