zsunbuf is a STREAMS module to turn off input buffering in the SunOS 4 zs
driver. It was written in the hope of getting flexfax to drive a Class 1
modem on a Sun.

As root, "make load" to install it.  You may wish to look at the Makefile
first!

Then apply faxd.patch to your flexfax sources and make a new faxd.
[Sam: already done in version 2.2 or later.]

If this fixes your Class 1 problems, you may wish to recompile zsunbuf
without -DDEBUG to prevent the console messages and add the modload
command to /etc/rc.local.

If it doesn't, you may wish to check that zsunbuf is doing something
to your zs driver -- see the file TESTING for further details.

Tim Rylance <tkr@puffball.demon.co.uk>, 21st April 1993.