> is there a reason why histograms are not saved after a replay?
> 
>    /* save histos if requested */
>    if (out_info.histo_dump && clp.online) {
>                               ^^^^^^^^^^
> 
> perhaps the && should be ||?

The original reason for that is the for running online, you want some histos for
monitoring after each run. For running offline, you specify a root output file via
"-o xxx.root" which contains trees AND histos. So the histos would there be twice
if you remove the "clp.online" from above.

Having "-o xxx.root" is IMHO a cleaner way, since you might want to analyze a run
in different ways (like using different calibrations). So what you do is specify
different "-o cal00123.root", "-o final00123.root" and so on, while with the
mechanism in eor() you always get the same file name. So try using "-o xxx.root"
and see if that fits your needs.