$picoide = "c:\\program files\\picoide" ;
$errfile = "build.out" ;
$err_sentinal = "b.err" ;

unlink($errfile) ;
open(X,">$errfile") || exit 2 ;
print X "Press Shift-F8 to build.\n" ;
close(X) ;

for (;;)  {
    system("\"$picoide\\picoide\" $errfile") ;
    open(E,"<exitstat") || exit 1 ;
    $status = scalar(<E>) ;
    $status =~ s/[\r\n]//g ;
    close(E) ;
    last if ($status ne "Build") ;
    unlink($err_sentinal) ;
    $status = system("build >$errfile") ;
    last unless (-r $err_sentinal) ;
}