Is there a way to set the global windows path environment variable programmatically (C++)?
As far as I can see, putenv sets it only for the current application.
Changing directly in the registry (HKLM\SYSTEM\CurrentControlSet\Control\Session Manager\Environment) is also an option though I would prefer API methods if there are?
MSDN Says:
Calling SetEnvironmentVariable has no effect on the system environment variables. To programmatically add or modify system environment variables, add them to the HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\Session Manager\Environment registry key, then broadcast a WM_SETTINGCHANGE message with lParam set to the string "Environment". This allows applications, such as the shell, to pick up your updates. Note that the values of the environment variables listed in this key are limited to 1024 characters.
As was pointed out earlier, to change the PATH at the machine level just change this registry entry:
HLM\SYSTEM\CurrentControlSet\Control\Session Manager\Environment
But you can also set the PATH at the user level by changing this registry entry:
HKEY_CURRENT_USER\Environment\Path
And you can also set the PATH at the application level by adding the application\Path details to this registry entry:
HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\App Paths\