Seems could be fixed very easily, Debian has this patch: https://salsa.debian.org/debian/shntool/-/commit/57efcd7b34c2107dd785c11d79dfcd4520b2bc41 shntool unfortunately didn't updated since 2009, so I guess it might make sense to look and probably take other patches Debian use: https://salsa.debian.org/debian/shntool/-/tree/master/debian/patches?ref_type=heads