Here is a lightly tested OO solution. 
package RegexInput;

sub new{
  my ($class,$file)=@_;
  my $fh;
  open $fh,$file;
  my $self = {
          FH=>$fh,
          leftover=>""
         };
  bless $self,$class;
}

sub get_line{
  my $self=shift;
  my $regex=shift;
  my $fh=$self->{FH};
  my $string=$self->{leftover};
  while (<$fh>) {
    $string.=$_;
    if ($string=~/$regex/s) {
      $self->{leftover}=$';
      return $string;
    }
  }
  $self->{leftover}="";
  return $string;
}

package main;
my $buf = new RegexInput($0);
while (my $line=$buf->get_line(qr/\n\}/)) {
  print $line,"\n","="x50,"\n";
}

[download]
OUTPUT: 
package RegexInput;

sub new{
  my ($class,$file)=@_;
  my $fh;
  open $fh,$file;
  my $self = {
          FH=>$fh,
          leftover=>""
         };
  bless $self,$class;
}

==================================================


sub get_line{
  my $self=shift;
  my $regex=shift;
  my $fh=$self->{FH};
  my $string=$self->{leftover};
  while (<$fh>) {
    #print $_;
    $string.=$_;
    if ($string=~/$regex/s) {
      $self->{leftover}=$';
      return $string;
    }
  }
  $self->{leftover}="";
  return $string;
}

==================================================


package main;
my $buf = new RegexInput($0);
while (my $line=$buf->get_line(qr/\n\}/)) {
  print $line,"\n","="x50,"\n";
}

==================================================


==================================================

[download]

In reply to Re: Regexing an input stream... by Anonymous Monk
in thread Regexing an input stream... by sergio

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