# SetEnv.pl sets system environment variable via NT registry.
# Written 15-oct-1998 by fhb out of frustration with CMD's limits.
# Usage: SetEnv varname [value]

#require "ctime.pl";
use Win32::Registry;

$bDebug = 0;
$sAppName = "SetEnv";
$sVersion = "1.0";

if ($bDebug) { print "dbg> ARGV == $#ARGV\n"; }
if ($#ARGV < 0) { &usage(); }

# here if at least 1 arg, so assume it's env variable:

$sItem = $ARGV[0];
$sKeySpec = "SYSTEM\\CurrentControlSet\\control\\Session Manager\\environment";
$key = undef;

if ($#ARGV == 0) {
  $main::HKEY_LOCAL_MACHINE->Open($sKeySpec,$key) || die "Open: $!";

  $key->QueryValueEx($sItem,$type,$sVal);
  $key->Close;
  
  if (length($sVal) > 0) { print "$sItem = $sVal\n"; }
  else { print "$sItem is undefined\n"; }
  }
if ($#ARGV == 1) {
  $sVal  = $ARGV[1];
  $main::HKEY_LOCAL_MACHINE->Open($sKeySpec,$key) || die "Open: $!";

  ### *** REG_SZ string type hardcoded below! *** ###

  $key->SetValueEx($sItem,0,REG_SZ,$sVal) || die "SetValueEx: $!";
  $key->Close;

  print "Environment variable $sItem set to $sVal\n";
  }

exit;

######## subroutines start here: #########

sub usage {
  print "$sAppName $sVersion: set (or report) a system environment variable.\n";
  printf("\nUsage: %s varname [value]\n",$sAppName);
  printf("\nif [value] omitted, %s reports current value\n",$sAppName);
  exit;
  }