cscript: add path in system %PATH%, no reboot required

add_to_system_path.js

var shell = WScript.CreateObject('WScript.Shell');
var envs = shell.Environment('SYSTEM');
var systemPath = envs('PATH');
var paths = systemPath.split(';');

if (WScript.Arguments.Count() != 1){
    WScript.StdErr.WriteLine('Error: one argument expected');
    WScript.StdErr.WriteLine('Paths in %PATH% :');
    for (i in paths){
        WScript.StdOut.WriteLine(paths[i]);
    }
    WScript.Quit(1);
}
var pathAdd = WScript.Arguments(0);

var found = false;
for (i in paths){
    //WScript.StdOut.WriteLine(paths[i]);
    if (pathAdd.toLowerCase() == paths[i].toLowerCase()){
        found = true;
        break;
    }
}

if (found) {
    WScript.StdOut.WriteLine('"' + pathAdd+'" already in %PATH%');
}
else {
    envs("PATH") = envs("PATH") + ";" + pathAdd;
    WScript.StdOut.WriteLine('"' + pathAdd+'" added to %PATH%');
    WScript.StdOut.WriteLine(envs("PATH"));
}

Usage:

cscript add_to_system_path.js C:\strawberry\perl\bin