my $buf = delete($self->{buf});
while (my $smsg = $self->{cb}->($ctx)) {
my $mref = $ctx->{-inbox}->msg_by_smsg($smsg) or next;
my $buf = delete($self->{buf});
while (my $smsg = $self->{cb}->($ctx)) {
my $mref = $ctx->{-inbox}->msg_by_smsg($smsg) or next;