Uniable to print sad.idx files

[lpabonv]

Hi, I've produced several saf.idx files from bam files, but when I want to print the saf file using the "realSFS print" it doesn´t work, it just prints me this:

-> Version of fname:filtered_unfolded_atsc.saf.idx is:2
-> Assuming .saf.gz file: filtered_unfolded_atsc.saf.gz
-> Assuming .saf.pos.gz: filtered_unfolded_atsc.saf.pos.gz
-> args: tole:0.000001 nthreads:4 maxiter:100 nsites:0 start:(null) chr:(null) start:-1 stop:-1 fname:filtered_unfolded_atsc.saf.idx fstout:(null) oldout:0 seed:1695239834 bootstrap:0
-> Will jump to multisaf printer and will only print intersecting sites between populations
[printMulti]
Aborted (core dumped)

It's the same for all files, although I try this in interactive sessions with a lot of resoruces from the cluster, it still doesn't work.
In the end what I need is to know the number of sites used (or retained) for the saf.idx file which was used to rpoduce a sfs file