🚀 go-pugleaf

PROBLEM:

Program A spools a file to disk and execute()s a command to type
the file to a device which prints it after some processing.

Program A runs at priority 0, device runs at priority 5.

Device hoggs processor, and Program A does bugger all, making the
spool fairly useless.

Thus Program A at priority 0, device at priority 0.

Works fine, except now, if Program A tries to write direct to device
with fprintf() calls, the system hangs (or seems to, I got bored).

This does _not_ happen if device priority is set to 5.

Note, I do not check the return code from fprintf(). Should I? What's
wrong with this? How do I get the two programs to talk to each other
politely without stepping on each others toes?

Regards Alan