open( my $fh, "<", $sigDataFile ) || die( "cannot open file - $!" );
  while( <$fh> ) {
     chomp;
     my( $key, $value ) = split(/=/, $_); # does = need to be escaped?
     ...
   }

##</code><code>##

  use Fcntl;
  use SDBM_File;

  tie( %hash, 'SDBM_File', 'temp_file_name', O_RDWR|O_CREAT, 0666 )
    or die "Couldn't tie SDBM file 'filename': $!; aborting";

  open( my $fh, "<", $sigDataFile ) || die( "cannot open file - $!" );
  while( <$fh> ) {
    chomp;
    my( $key, $value ) = split( /=/, $_ );
    $hash{$key} = $value;
    ...
  }