sub1()
{
  my $variables;
  my $buff;
  code
  code
  code

  {
    local *STDOUT;
    open( STDOUT, '>', \$buf ) or die "Write to buffer   ailed\n";
    mysub();
  }

  print "buffer: $buf\n";

  more code

}


sub mysub
{
  print "mysub output\n";
}