[sane-devel] how do you use "saned -d and -s?

[ToddAndMargo]

Dear list,

Scientific Linux 7.4 (RHEL Clone based on CentOS)

# rpm -qa sane-backends
sane-backends-1.0.24-9.el7.x86_64

# ps ax | grep [s]aned
29857 ?        Ss     0:00 /usr/sbin/saned -a saned -d128


How do I use
/usr/sbin/saned -a saned -d128
or -s
to see why a scanner command is crashing?

Simple Scan works.

PDF Studio requires saned be running and does find the scanner,
gives me the following error:

com.qoppa.uk.b.b.e.m: Invalid operation
	at com.qoppa.uk.b.b.e.k.b(Unknown Source)
	at com.qoppa.uk.b.b.b.o.fc(Unknown Source)
	at com.qoppa.uk.b.b.b.o.wb(Unknown Source)
	at com.qoppa.pdfStudio.k.p.d(Unknown Source)
	at com.qoppa.pdfStudio.k.p.e(Unknown Source)
	at com.qoppa.pdfStudio.k.p.s(Unknown Source)
	at com.qoppa.pdfStudio.l.vd.dae(Unknown Source)
	at com.qoppa.pdfStudio.l.vd.fzd(Unknown Source)
	at com.qoppa.pdfStudio.l.vd$14.run(Unknown Source)
	at java.lang.Thread.run(Thread.java:748)


Many thanks,
-T