Neither get_select_fd() nor non-blocking

I've realized that backends might not provide neither a file
descriptor 
for select() nor non-blocking mode. Why is this allowed? I
guess this 
means that applications, such as xsane, must use a separate
thread or 
process to read the data? IMHO, this puts a lot of
unnecessary burden on 
the application programmer. How common is it with backends
with neither a 
select FD nor non-blocking mode? How about adjusting the
standard so that 
backends must at least support one of these?

Regards, 
-- 
Peter Åstrand		ThinLinc Chief Developer
Cendio AB		http://www.cendio.se
Teknikringen 3
583 30 Linköping	Phone: +46-13-21 46 00-- 
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