[news.eclipse.platform] Re: how to set system environment variables prog

[paubessard@xxxxxxxxxx (Philippe)]

Hi Joneo,

The Microsoft setx.exe utility, which have from the Windows NT 4.0 
resource kit, allows you to change an environment variable from a command 
line such that it will change the global environment settings. The version 
I have (1.0a 5/31/96) appears to work fine on Windows XP SP2. 

Here is the setx's help string :

 SETX: This program is used to set values in the environment of the 
machine or
 currently logged on user using one of three modes. Without SETX, there 
is no
 method for settings values directly into the master environment for 
Windows
 NT. These are configureable only through Control Panel or through the
 Registry Editor. The SET command, which is internal to the command
 interpreter, sets variables only into the environment of the current 
window.
 SETX allows you to set values for variables in either the user or 
computer
 environment from one of three sources: Command Line Mode, Registry Mode, 
and
 File Mode.

You can download it from :

http://download.microsoft.com/download/win2000platform/setx/1.00.0.1/nt5/en-us/setx_setup.exe

Here is my method to read Window's environment variables (wich use the SET 
command):

private static Properties getEnvVars() throws Throwable {
 Properties envVars = new Properties();
 if ( envVars != null ) {
   Runtime r = Runtime.getRuntime();
   if ( r != null ) {
     Process p = null;
     String OS = System.getProperty("os.name").toLowerCase();
     if (OS.indexOf("windows 9") > -1) {
       p = r.exec("command.com /c set");
     } else if ((OS.indexOf("nt") > -1)
             || (OS.indexOf("windows 20") > -1)
             || (OS.indexOf("windows xp") > -1)) {
       p = r.exec("cmd.exe /c set" );
     } // no linux support !
     if ( p != null ) {
       BufferedReader br = new BufferedReader( new InputStreamReader( 
p.getInputStream() ) );
       if ( br != null ) {
         String line;
         while ((line = br.readLine()) != null) {
           int idx = line.indexOf('=');
           envVars.setProperty( line.substring(0, idx), 
line.substring(idx + 1) );
         }
         return envVars;
       }
     }
   }
 }
 return null;		
} // end of getEnvVars()

And a method to set an environment variable (wich use the SETX command):

private static void setEnvVars( String _variable, String _value ) throws 
Throwable {
 Runtime r = Runtime.getRuntime();
 String OS = System.getProperty("os.name").toLowerCase();
 if (OS.indexOf("windows 9") > -1) {
   r.exec("command.com /c setx.exe "+_variable+" "+_value);
 } else if ((OS.indexOf("nt") > -1)
         || (OS.indexOf("windows 20") > -1)
         || (OS.indexOf("windows xp") > -1)) {
   r.exec("cmd.exe /c setx.exe "+_variable+" "+_value);
 }
 // no linux support !
} // end of setEnvVars()

Of course, your code becomes not-portable...
--
Philippe